Communication system

ABSTRACT

A communication system in which when judging to have received an RRC message from a communication terminal device, a base station device, for example, HeNB checks an MTCD indicator to be mapped to the received RRC message. Then, when judging that the UE that has transmitted the RRC message received is an MTCD being a device for machine type communication (MTC) from the checked MTCD indicator, the HeNB performs a concentration process on the data from the MTCD to the core network.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. patent application Ser. No.15/067,649 filed Mar. 11, 2016, which is a divisional of U.S. patentapplication Ser. No. 13/877,302 filed Apr. 1, 2013, which is a NationalStage of PCT/JP2011/071980 filed Sep. 27, 2011, and claims priority toJapanese Patent Application No. 2010-223641 filed Oct. 1, 2010. Theentire contents of each of which are incorporated herein by reference.

TECHNICAL FIELD

The present invention relates to a communication system in which a basestation device performs radio communication with a plurality ofcommunication terminal devices.

BACKGROUND ART

Commercial service of a wideband code division multiple access (W-CDMA)system among so-called third-generation communication systems has beenoffered in Japan since 2001. In addition, high speed downlink packetaccess (HSDPA) service for achieving higher-speed data transmissionusing a downlink has been offered by adding a channel for packettransmission (high speed-downlink shared channel (HS-DSCH)) to thedownlink (dedicated data channel, dedicated control channel). Further,in order to increase the speed of data transmission in an uplinkdirection, service of a high speed uplink packet access (HSUPA) systemhas been offered. W-CDMA is a communication system defined by the 3rdgeneration partnership project (3GPP) that is the standard organizationregarding the mobile communication system, where the specifications ofRelease 8 version are produced.

Further, 3GPP is studying new communication systems referred to as longterm evolution (LTE) regarding radio areas and system architectureevolution (SAE) regarding the overall system configuration including acore network (merely referred to as network as well) as communicationsystems independent of W-CDMA. This communication system is alsoreferred to as 3.9 generation (3.9 G) system.

In the LTE, an access scheme, a radio channel configuration and aprotocol are totally different from those of the current W-CDMA(HSDPA/HSUPA). For example, as to the access scheme, code divisionmultiple access is used in the W-CDMA, whereas in the LTE, orthogonalfrequency division multiplexing (OFDM) is used in a downlink directionand single career frequency division multiple access (SC-FDMA) is usedin an uplink direction. In addition, the bandwidth is 5 MHz in theW-CDMA, while in the LTE, the bandwidth can be selected from 1.4 MHz, 3MHz, 5 MHz, 10 MHz, 15 MHz and 20 MHz per base station. Further,differently from the W-CDMA, circuit switching is not provided but apacket communication system is only provided in the LTE.

The LTE is defined as a radio access network independent of the W-CDMAnetwork because its communication system is configured with a new corenetwork different from a core network (general packet radio service:GPRS) of the W-CDMA. Therefore, for differentiation from the W-CDMAcommunication system, a base station that communicates with a userequipment (UE) and a radio network controller that transmits/receivescontrol data and user data to/from a plurality of base stations arereferred to as an E-UTRAN NodeB (eNB) and an evolved packet core (EPC)or access gateway (aGW), respectively, in the LTE communication system.Unicast service and evolved multimedia broadcast multicast service(E-MBMS service) are provided in this LTE communication system. TheE-MBMS service is broadcast multimedia service, which is merely referredto as MBMS in some cases. Bulk broadcast contents such as news, weatherforecast and mobile broadcast are transmitted to a plurality of userequipments. This is also referred to as point to multipoint service.

Non-Patent Document 1 (Chapter 4.6.1) describes the current decisions by3GPP regarding an overall architecture in the LTE system. The overallarchitecture is described with reference to FIG. 1. FIG. 1 is a diagramillustrating the configuration of the LTE communication system. Withreference to FIG. 1, the evolved universal terrestrial radio access(E-UTRAN) is composed of one or a plurality of base stations 102,provided that a control protocol for a user equipment 101 such as aradio resource control (RRC) and user planes such as a packet dataconvergence protocol (PDCP), radio link control (RLC), medium accesscontrol (MAC) and physical layer (PHY) are terminated in the basestation 102.

The base stations 102 perform scheduling and transmission of pagingsignal (also referred to as paging messages) notified from a mobilitymanagement entity (MME) 103. The base stations 102 are connected to eachother by means of an X2 interface. In addition, the base stations 102are connected to an evolved packet core (EPC) by means of an S1interface. More specifically, the base station 102 is connected to themobility management entity (MME) 103 by means of an S1_MME interface andconnected to a serving gateway (S-GW) 104 by means of an S1_U interface.

The MME 103 distributes the paging signal to a plurality of or a singlebase station 102. In addition, the MME 103 performs mobility control ofan idle state. When the user equipment is in the idle state and anactive state, the MME 103 manages a list of tracking areas.

The S-GW 104 transmits/receives user data to/from one or a plurality ofbase stations 102. The S-GW 104 serves as a local mobility anchor pointin handover between base stations. Moreover, a PDN gateway (P-GW) isprovided in the EPC, which performs per-user packet filtering and UE-IDaddress allocation.

The control protocol RRC between the user equipment 101 and the basestation 102 performs broadcast, paging, RRC connection management andthe like. The states of the base station and the user equipment in RRCare classified into RRC_IDLE and RRC_CONNECTED. In RRC_IDLE, public landmobile network (PLMN) selection, system information (SI) broadcast,paging, cell reselection, mobility and the like are performed. InRRC_CONNECTED, the user equipment has RRC connection, is capable oftransmitting/receiving data to/from a network, and performs, forexample, handover (HO) and measurement of a neighbor cell.

The current decisions by 3GPP regarding the frame configuration in theLTE system described in Non-Patent Document 1 (Chapter 5) are describedwith reference to FIG. 2. FIG. 2 is a diagram illustrating theconfiguration of a radio frame used in the LTE communication system.With reference to FIG. 2, one radio frame is 10 ms. The radio frame isdivided into ten equally sized subframes. The subframe is divided intotwo equally sized slots. The first and sixth subframes contain adownlink synchronization signal (SS) per each radio frame. Thesynchronization signals are classified into a primary synchronizationsignal (P-SS) and a secondary synchronization signal (S-SS).

Multiplexing of channels for multimedia broadcast multicast servicesingle frequency network (MBSFN) and for non-MBSFN is performed on aper-subframe basis. MBSFN transmission is a simulcast transmissiontechnique realized by simultaneous transmission of the same waveformsfrom a plurality of cells. The MBSFN transmission from a plurality ofcells in the MBSFN area is seen as a single transmission by a userequipment. The MBSFN is a network that supports such MBSFN transmission.Hereinafter, a subframe for MBSFN transmission is referred to as MBSFNsubframe.

Non-Patent Document 2 describes a signaling example when MBSFN subframesare allocated. FIG. 3 is a diagram illustrating the configuration of theMBSFN frame. With reference to FIG. 3, the MBSFN subframes are allocatedfor each MBSFN frame. The MBSFN frame is repeated in allocation periods(radio frame allocation periods). The MBSFN subframe is a subframeallocated for the MBSFN in a radio frame defined by the allocationperiod and the allocation offset (radio frame allocation offset), andserves to transmit multimedia data. The radio frame satisfying Equation(1) below is a radio frame including the MBSFN subframes.

SFN mod radioFrameAllocationPeriod=radioFrameAllocationOffset  (1)

The MBSFN subframe is allocated with six bits. The leftmost bit definesthe MBSFN allocation for the second subframe (#1). The second bit, thirdbit, fourth bit, fifth bit, and sixth-bit define the MBSFN allocationfor the third subframe (#2), fourth subframe (#3), seventh subframe(#6), eighth subframe (#7), and ninth subframe (#8), respectively. Thecase where the bit indicates “one” represents that the correspondingsubframe is allocated for the MBSFN.

Non-Patent Document 1 (Chapter 5) describes the current decisions by3GPP regarding the channel configuration in the LTE system. It isassumed that the same channel configuration is used in a closedsubscriber group cell (CSG cell) as that of a non-CSG cell. Physicalchannels are described with reference to FIG. 4. FIG. 4 is a diagramillustrating physical channels used in the LTE communication system.With reference to FIG. 4, a physical broadcast channel (PBCH) 401 is adownlink channel transmitted from the base station 102 to the userequipment 101. A BCH transport block is mapped to four subframes withina 40 ms interval. There is no explicit signaling indicating 40 mstiming. A physical control format indicator channel (PCFICH) 402 istransmitted from the base station 102 to the user equipment 101. ThePCFICH notifies the number of OFDM symbols used for PDCCHs from the basestation 102 to the user equipment 101. The PCFICH is transmitted in eachsubframe.

A physical downlink control channel (PDCCH) 403 is a downlink channeltransmitted from the base station 102 to the user equipment 101. ThePDCCH notifies the resource allocation, hybrid automatic repeat request(HARD) information related to DL-SCH (downlink shared channel that isone of the transport channels shown in FIG. 5 described below) and thePCH (paging channel that is one of the transport channels shown in FIG.5). The PDCCH carries an uplink scheduling grant. The PDCCH carriesacknowledgement (Ack)/negative acknowledgement (Nack) that is a responsesignal to uplink transmission. The PDCCH is referred to as an L1/L2control signal as well.

A physical downlink shared channel (PDSCH) 404 is a downlink channeltransmitted from the base station 102 to the user equipment 101. ADL-SCH (downlink shared channel) that is a transport channel and a PCHthat is a transport channel are mapped to the PDSCH. A physicalmulticast channel (PMCH) 405 is a downlink channel transmitted from thebase station 102 to the user equipment 101. A multicast channel (MCH)that is a transport channel is mapped to the PMCH.

A physical uplink control channel (PUCCH) 406 is an uplink channeltransmitted from the user equipment 101 to the base station 102. ThePUCCH carries Ack/Nack that is a response signal to downlinktransmission. The PUCCH carries a channel quality indicator (CQI)report. The CQI is quality information indicating the quality ofreceived data or channel quality. In addition, the PUCCH carries ascheduling request (SR). A physical uplink shared channel (PUSCH) 407 isan uplink channel transmitted from the user equipment 101 to the basestation 102. A UL-SCH (uplink shared channel that is one of thetransport channels shown in FIG. 5) is mapped to the PUSCH.

A physical hybrid ARQ indicator channel (PHICH) 408 is a downlinkchannel transmitted from the base station 102 to the user equipment 101.The PHICH carries Ack/Nack that is a response to uplink transmission. Aphysical random access channel (PRACH) 409 is an uplink channeltransmitted from the user equipment 101 to the base station 102. ThePRACH carries a random access preamble.

A downlink reference signal is a known symbol in a mobile communicationsystem. The physical layer measurement objects of a user equipmentinclude reference symbol received power (RSRP).

The transport channel described in Non-Patent Document 1 (Chapter 5) isdescribed with reference to FIG. 5. FIG. 5 is a diagram illustratingtransport channels used in the LTE communication system. Part (A) ofFIG. 5 shows mapping between a downlink transport channel and a downlinkphysical channel. Part (B) of FIG. 5 shows mapping between an uplinktransport channel and an uplink physical channel.

A broadcast channel (BCH) is broadcast to the entire coverage of a basestation (cell) regarding the downlink transport channel. The BCH ismapped to the physical broadcast channel (PBCH).

Retransmission control according to a hybrid ARQ (HARD) is applied to adownlink shared channel (DL-SCH). The DL-SCH enables broadcast to theentire coverage of the base station (cell). The DL-SCH supports dynamicor semi-static resource allocation. The semi-static resource allocationis also referred to as persistent scheduling. The DL-SCH supportsdiscontinuous reception (DRX) of a user equipment for enabling the userequipment to save power. The DL-SCH is mapped to the physical downlinkshared channel (PDSCH).

The paging channel (PCH) supports DRX of the user equipment for enablingthe user equipment to save power. The PCH is required to broadcast tothe entire coverage of the base station (cell). The PCH is mapped tophysical resources such as the physical downlink shared channel (PDSCH)that can be used dynamically for traffic or physical resources such asthe physical downlink control channel (PDCCH) of the other controlchannel.

The multicast channel (MCH) is used for broadcast to the entire coverageof the base station (cell). The MCH supports SFN combining of MBMSservice (MTCH and MCCH) in multi-cell transmission. The MCH supportssemi-static resource allocation. The MCH is mapped to the PMCH.

Retransmission control according to a hybrid ARQ (HARQ) is applied to anuplink shared channel (UL-SCH). The UL-SCH supports dynamic orsemi-static resource allocation. The UL-SCH is mapped to the physicaluplink shared channel (PUSCH).

A random access channel (RACH) shown in part (B) of FIG. 5 is limited tocontrol information. The RACH involves a collision risk. The RACH ismapped to the physical random access channel (PRACH).

The HARQ is described. The HARQ is the technique for improving thecommunication quality of a channel by combination of automatic repeatrequest (ARQ) and error correction (forward error correction). The HARQhas an advantage that error correction functions effectively byretransmission even for a channel whose communication quality changes.In particular, it is also possible to achieve further qualityimprovement in retransmission through combination of the receptionresults of the first transmission and the reception results of theretransmission.

An example of the retransmission method is described. In a case wherethe receiver fails to successfully decode the received data, in otherwords, in a case where a cyclic redundancy check (CRC) error occurs(CRC=NG), the receiver transmits “Nack” to the transmitter. Thetransmitter that has received “Nack” retransmits the data. In a casewhere the receiver successfully decodes the received data, in otherwords, in a case where a CRC error does not occur (CRC=OK), the receivertransmits “AcK” to the transmitter. The transmitter that has received“Ack” transmits the next data.

Examples of the HARQ system include chase combining. In chase combining,the same data sequence is transmitted in the first transmission andretransmission, which is the system for improving gains by combining thedata sequence of the first transmission and the data sequence of theretransmission in retransmission. This is based on the idea that correctdata is partially included even if the data of the first transmissioncontains an error, and highly accurate data transmission is enabled bycombining the correct portions of the first transmission data and theretransmission data. Another example of the HARQ system is incrementalredundancy (IR). The IR is aimed to increase redundancy, where a paritybit is transmitted in retransmission to increase the redundancy bycombining the first transmission and retransmission, to thereby improvethe quality by an error correction function.

A logical channel described in Non-Patent Document 1 (Chapter 6) isdescribed with reference to FIG. 6. FIG. 6 is a diagram illustratinglogical channels used in an LTE communication system. Part (A) of FIG. 6shows mapping between a downlink logical channel and a downlinktransport channel. Part (B) of FIG. 6 shows mapping between an uplinklogical channel and an uplink transport channel.

A broadcast control channel (BCCH) is a downlink channel for broadcastsystem control information. The BCCH that is a logical channel is mappedto the broadcast channel (BCH) or downlink shared channel (DL-SCH) thatis a transport channel.

A paging control channel (PCCH) is a downlink channel for transmittingpaging signals. The PCCH is used when the network does not know the celllocation of a user equipment. The PCCH that is a logical channel ismapped to the paging channel (PCH) that is a transport channel.

A common control channel (CCCH) is a channel for transmission controlinformation between user equipments and a base station. The CCCH is usedin a case where the user equipments have no RRC connection with thenetwork. In a downlink direction, the CCCH is mapped to the downlinkshared channel (DL-SCH) that is a transport channel. In an uplinkdirection, the CCCH is mapped to the uplink shared channel (UL-SCH) thatis a transport channel.

A multicast control channel (MCCH) is a downlink channel forpoint-to-multipoint transmission. The MCCH is a channel used fortransmission of MBMS control information for one or several MTCHs from anetwork to a user equipment. The MCCH is a channel used only by a userequipment during reception of the MBMS. The MCCH is mapped to thedownlink shared channel (DL-SCH) or multicast channel (MCH) that is atransport channel.

A dedicated control channel (DCCH) is a channel that transmits dedicatedcontrol information between a user equipment and a network. The DCCH ismapped to the uplink shared channel (UL-SCH) in uplink and mapped to thedownlink shared channel (DL-SCH) in downlink.

A dedicated traffic channel (DTCH) is a point-to-point communicationchannel for transmission of user information to a dedicated userequipment. The DTCH exists in uplink as well as downlink. The DTCH ismapped to the uplink shared channel (UL-SCH) in uplink and mapped to thedownlink shared channel (DL-SCH) in downlink.

A multicast traffic channel (MTCH) is a downlink channel for trafficdata transmission from a network to a user equipment. The MTCH is achannel used only by a user equipment during reception of the MBMS. TheMTCH is mapped to the downlink shared channel (DL-SCH) or multicastchannel (MCH).

GCI represents a global cell identity. A closed subscriber group cell(CSG cell) is introduced in the LTE and universal mobiletelecommunication system (UMTS). The CSG is described below (see Chapter3.1 of Non-Patent Document 3). The closed subscriber group (CSG) is acell in which subscribers who are allowed to use are specified by anoperator (cell for specific subscribers).

The specified subscribers are allowed to access one or more E-UTRANcells of a public land mobile network (PLMN). One or more E-UTRAN cellsin which the specified subscribers are allowed access are referred to as“CSG cell(s)”. Note that access is limited in the PLMN. The CSG cell ispart of the PLMN that broadcasts a specific CSG identity (CSG ID;CSG-ID). The authorized members of the subscriber group who haveregistered in advance access the CSG cells using the CSG-ID that is theaccess permission information.

The CSG-ID is broadcast by the CSG cell or cells. A plurality of CSG-IDsexist in a mobile communication system. The CSG-IDs are used by userequipments (UEs) for making access from CSG-related members easier.

The locations of user equipments are tracked based on an area composedof one or more cells. The locations are tracked for enabling tracking ofthe locations of user equipments and calling (calling of userequipments) even in an idle state. An area for tracing locations of userequipments is referred to as a tracking area.

A CSG whitelist is a list stored in a universal subscriber identitymodule (USIM) in which all CSG IDs of the CSG cells to which thesubscribers belong are recorded. The CSG whitelist is also referred toas an allowed CSG ID list in some cases.

A “suitable cell” is described below (see Chapter 4. 3 of Non-PatentDocument 3). The “suitable cell” is a cell on which a UE camps to obtainnormal service. Such a cell shall fulfill the following conditions (1)and (2).

(1) The cell is part of the selected PLMN or the registered PLMN, orpart of the PLMN of an “equivalent PLMN list”.

(2) According to the latest information provided by a non-access stratum(NAS), the cell shall further fulfill the following conditions (a) to(d):

(a) the cell is not a barred cell;

(b) the cell is part of at least one tracking area (TA), not part of thelist of “forbidden LAs for roaming”, where the cell needs to fulfill (1)above;

(c) the cell shall fulfill the cell selection criteria; and

(d) for a cell specified as CSG cell by system information (SI), theCSG-ID is part of a “CSG whitelist” of the UE (contained in the CSGwhitelist of the UE).

An “acceptable cell” is described below (see Chapter 4.3 of Non-PatentDocument 3). This is the cell on which a UE camps to obtain limitedservice (emergency calls). Such a cell shall fulfill the all followingrequirements. That is, the minimum required set for initiating anemergency call in an E-UTRAN network are as follows: (1) the cell is nota barred cell; and (2) the cell fulfills the cell selection criteria.

Camping on a cell represents the state where a UE has completed the cellselection/reselection process and the UE has selected a cell formonitoring the system information and paging information.

3GPP is studying base stations referred to as Home-NodeB (Home-NB; HNB)and Home-eNodeB (Home-eNB; HeNB). HNB/HeNB is a base station for, forexample, household, corporation or commercial access service inUTRAN/E-UTRAN. Non-Patent Document 4 discloses three different modes ofthe access to the HeNB and HNB. Specifically, those are an open accessmode, a closed access mode and a hybrid access mode.

The respective modes have the following characteristics. In the openaccess mode, the HeNB and HNB are operated as a normal cell of a normaloperator. In the closed access mode, the HeNB and HNB are operated as aCSG cell. The CSG cell is a cell where only CSG members are allowedaccess. In the hybrid access mode, non-CSG members are allowed access atthe same time. In other words, a cell in the hybrid access mode (alsoreferred to as hybrid cell) is the cell that supports both the openaccess mode and the closed access mode.

3GPP is discussing that all physical cell identities (PCIs) are split(referred to as PCI-split) into ones reserved for CSG cells and theothers reserved for non-CSG cells (see Non-Patent Document 5). Further,3GPP is discussing that the PCI split information is broadcast in thesystem information from the base station to the user equipments beingserved thereby. The basic operation of a user equipment using PCI splitis disclosed. The user equipment that does not have the PCI splitinformation needs to perform cell search using all PCIs (for example,using all 504 codes). On the other hand, the user equipment that has thePCI split information is capable of performing cell search using the PCIsplit information.

Further, 3GPP is pursuing specifications standard of long term evolutionadvanced (LTE-A) as Release 10 (see Non-Patent Document 6 and Non-PatentDocument 7).

As to the LTE-A system, it is studied that a relay (relay node (RN)) issupported for achieving a high data rate, high cell-edge throughput, newcoverage area, and the like. The relay node is wirelessly connected tothe radio-access network via a donor cell (Donor eNB; DeNB). The network(NW)-to-relay node link shares the same frequency band with thenetwork-to-UE link within the range of the donor cell. In this case, theUE in Release 8 can also be connected to the donor cell. The linkbetween a donor cell and a relay node is referred to as a backhaul link,and the link between the relay node and the UE is referred to as anaccess link.

As the method of multiplexing a backhaul link in frequency divisionduplex (FDD), the transmission from a DeNB to an RN is performed at adownlink (DL) frequency band, and the transmission from an RN to a DeNBis performed at an uplink (UL) frequency band. As the method of dividingresources in a relay, a link from a DeNB to an RN and a link from an RNto a UE are time-division multiplexed at one frequency, and a link froman RN to a DeNB and a link from a UE to an RN are also time-divisionmultiplexed at one frequency band. Accordingly, in a relay, thetransmission of the relay is prevented from interfering the reception ofthe own relay.

3GPP is studying not only a normal eNB (macro cell) but also so-calledlocal nodes such as pico eNB (pico cell), HeNB/HNB/CSG cell, node forhotzone cells, relay node, and remote radio head (RRH).

The local nodes are installed so as to complement a macro cell inresponse to requests for various services such as high speed andlarge-capacity communication. It is required to install a large numberof HeNBs in shopping malls, apartment buildings, schools, companies andthe like. This leads to a case in which a HeNB is installed in acoverage of a macro cell. In a case where the HeNB is installed in thecoverage of the macro cell, interference occurs among the macro cell,HeNB, user equipment (UE), and the like. The above-mentionedinterference hinders the communication between the user equipment (UE)and the macro cell or HeNB, which reduces a data rate. Further increasedinterference power disables communication. This requires the method ofpreventing the interference occurring in a situation in which a macrocell and local nodes are installed to coexist and optimizing thecommunication quality.

3GPP is pursuing the study of the machine type communication (MTC)technique (see Non-Patent Document 8). A large number of MTC devices(MTCDs) are conceivable. In MTC service, there occurs a situation inwhich data is communicated from a large number of MTCDs or to a largenumber of MTCDs at the same time. This causes a problem that a corenetwork is congested.

In order to solve the above-mentioned problem, Non-Patent Document 9discloses that an eNB holds back and aggregates signaling messagescommon to MTCDs of the same MTCD group, whereby the signaling messagesare compacted.

PRIOR ART DOCUMENTS Non-Patent Documents

-   Non-Patent Document 1: 3GPP TS 36.300 V10.0.0 Chapter 4.6.1, Chapter    4.6.2, Chapter 5, Chapter 6, Chapter 10.1.2, Chapter 10.7-   Non-Patent Document 2: 3GPP TS 36.331 V9.3.0-   Non-Patent Document 3: 3GPP TS 36.304 V9.3.0 Chapter 3.1, Chapter    4.3, Chapter 5.2.4-   Non-Patent Document 4: 3GPP S1-083461-   Non-Patent Document 5: 3GPP R2-082899-   Non-Patent Document 6: 3GPP TR 36.814 V9.0.0-   Non-Patent Document 7: 3GPP TR 36.912 V9.0.0-   Non-Patent Document 8: 3GPP TS 22.368 V2.0.0-   Non-Patent Document 9: 3GPP S2-103186

SUMMARY OF INVENTION Problem to be Solved by the Invention

As described above, Non-Patent Document 9 discloses that an eNB holdsback and aggregates signaling messages common to MTCDs of the same MTCDgroup, whereby the signaling messages are compacted.

However, in a case where a large number of MTCD groups to be served byan eNB are located, even if the method disclosed in Non-Patent Document9 is used, the above-mentioned problem that the core network iscongested arises again.

An object of the present invention is to provide a communication systemcapable of mitigating, even if a large number of MTCD groups to beserved by an eNB are located, the congested state of a core network in asituation in which the data is required to be communicated from thelarge number of MTCDs or to the large number of MTCDs at the same time.

Means to Solve the Problem

A communication system according to the present invention includes abase station device connected to a core network and a plurality ofterminal device groups including communication terminal devicesconnected to the base station device so as to perform radiocommunication, wherein upon reception of data transmitted from thecommunication terminal devices to the core network, the base stationdevice performs a concentration process of concentrating the receiveddata on the terminal device groups and transmits the data obtainedthrough the concentration process to the core network.

Effects of the Invention

According to the communication system of the present invention, whenreceiving the data transmitted from the plurality of communicationterminal devices to the core network, the base station device performsthe concentration process of concentrating the received data on theplurality of terminal device groups and transmits the data obtainedthrough the concentration process to the core network. The concentrationprocess is performed on a plurality of terminal device groups in thismanner, so that even in a case where a large number of terminal devicegroups are located to be served by a base station device, the number ofcommunication times from a base station device to a core network oramount of data can be reduced. Accordingly, even in a case where a largenumber of terminal device groups to be served by a base station deviceare located, it is possible to mitigate the congestion of the corenetwork in a situation in which data needs to be communicated with alarge number of communication terminal devices included therein.

Further, the data to be transmitted from the communication terminaldevice to the core network is transmitted to the core network after theconcentration process by the base station device. Accordingly, even in acase where the communication terminal device is installed in a poorradio environment, communication with the communication terminal deviceis allowed, where the base station device serves as an origin. This doesnot require to separately provide, for example, a device such as aconcentrator between the communication terminal device and the basestation device, so that the communication system can be prevented frombecoming complicated.

These and other objects, features, aspects and advantages of the presentinvention will become more apparent from the following detaileddescription of the present invention when taken in conjunction with theaccompanying drawings.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a diagram illustrating the configuration of an LTEcommunication system.

FIG. 2 is a diagram illustrating the configuration of a radio frame usedin the LTE communication system.

FIG. 3 is a diagram illustrating the configuration of an MBSFN frame.

FIG. 4 is a diagram illustrating physical channels used in the LTEcommunication system.

FIG. 5 is a diagram illustrating transport channels used in the LTEcommunication system.

FIG. 6 is a diagram illustrating logical channels used in the LTEcommunication system.

FIG. 7 is a block diagram showing the overall configuration of an LTEmobile communication system currently under discussion of 3GPP.

FIG. 8 is a block diagram showing the configuration of a user equipment(user equipment 71 of FIG. 7) according to the present invention.

FIG. 9 is a block diagram showing the configuration of a base station(base station 72 of FIG. 7) according to the present invention.

FIG. 10 is a block diagram showing the configuration of an MME (MME unit73 of FIG. 7) according to the present invention.

FIG. 11 is a block diagram showing the configuration of a HeNBGW 74shown in FIG. 7 that is a HeNBGW according to the present invention.

FIG. 12 is a flowchart showing an outline from a cell search to an idlestate operation performed by a user equipment (UE) in the LTEcommunication system.

FIG. 13 is a diagram illustrating an example of an MTC architectureunder discussion of 3GPP.

FIG. 14 is a diagram showing a protocol stack of control data between aUE and an MME in a conventional technique.

FIG. 15 is a diagram showing a protocol stack of control data between anMTCD and an MME in a first embodiment.

FIG. 16 is a flowchart showing a procedure by a HeNB regarding aconcentration process in the first embodiment.

FIG. 17 is a diagram showing a sequence of a mobile communication systemin the first embodiment.

FIG. 18 is a flowchart showing the procedure by a HeNB regarding aconcentration process in a first modification of the first embodiment.

FIG. 19 is a diagram showing a sequence of a mobile communication systemin a second modification of the first embodiment.

FIG. 20 is a diagram showing a sequence of a mobile communication systemin a third modification of the first embodiment.

FIG. 21 is a diagram showing a sequence of a mobile communication systemin a fourth modification of the first embodiment.

FIG. 22 is a diagram showing a sequence of a mobile communication systemin a second embodiment.

FIG. 23 is another diagram showing the sequence of the mobilecommunication system in the second embodiment.

FIG. 24 is a diagram showing a sequence of a mobile communication systemin a first modification of the second embodiment.

FIG. 25 is a diagram showing a sequence of a mobile communication systemin a fourth modification of the second embodiment.

FIG. 26 is a diagram showing a sequence of a mobile communication systemin a third embodiment.

FIG. 27 is a diagram showing a sequence of a mobile communication systemin a fourth embodiment.

FIG. 28 is a diagram showing a sequence of a mobile communication systemin a fifth embodiment.

FIG. 29 is a diagram showing the sequence of the mobile communicationsystem in a first modification of the fifth embodiment.

FIG. 30 shows a diagram showing a location for describing a currentpaging method.

FIG. 31 is a diagram showing a sequence of a mobile communication systemfor describing unused radio resources in a case where the thirdembodiment is executed.

FIG. 32 is another diagram showing the sequence of the mobilecommunication system for describing unused radio resources in the casewhere the third embodiment is executed.

FIG. 33 is a diagram showing a sequence of the mobile communicationsystem for describing unused radio resources in a case where the fourthembodiment is executed.

FIG. 34 is another diagram showing the sequence of the mobilecommunication system for describing unused radio resources in the casewhere the fourth embodiment is executed.

FIG. 35 is a diagram showing a sequence of a mobile communication systemin a seventh embodiment.

FIG. 36 is another diagram showing the sequence of the mobilecommunication system in the seventh embodiment.

FIG. 37 is a diagram showing another sequence of the mobilecommunication system in the seventh embodiment.

FIG. 38 is another diagram showing the another sequence of the mobilecommunication system in the seventh embodiment.

FIG. 39 is a diagram showing still another sequence of the mobilecommunication system in the seventh embodiment.

FIG. 40 is another diagram showing the still another sequence of themobile communication system in the seventh embodiment.

FIG. 41 is a diagram showing yet still another sequence of the mobilecommunication system in the seventh embodiment.

FIG. 42 is another diagram showing the yet still another sequence of themobile communication system in the seventh embodiment.

FIG. 43 is a diagram showing a sequence of a mobile communication systemin a first modification of the seventh embodiment.

FIG. 44 is another diagram showing the sequence of the mobilecommunication system in the first modification of the seventhembodiment.

EMBODIMENTS FOR CARRYING OUT THE INVENTION First Embodiment

FIG. 7 is a block diagram showing an overall configuration of an LTEmobile communication system, which is currently under discussion of3GPP. Currently, 3GPP is studying an overall system configurationincluding closed subscriber group (CSG) cells (Home-eNodeBs (Home-eNB;HeNB) of E-UTRAN, Home-NB (HNB) of UTRAN) and non-CSG cells (eNodeB(eNB) of E-UTRAN, NodeB (NB) of UTRAN, and BSS of GERAN) and, as toE-UTRAN, is proposing the configuration as shown in FIG. 7 (see Chapter4.6.1 of Non-Patent Document 1).

FIG. 7 is described. A user terminal device (hereinafter, referred to as“user equipment” or “UE”) 71 is capable of performing radiocommunication with a base station device (hereinafter, referred to as“base station”) 72 and transmits/receives signals through radiocommunication. The user terminal device is equivalent to a communicationterminal device. Hereinafter, the user terminal device is referred to as“communication terminal” in some cases. The base stations 72 areclassified into an eNB 72-1 that is a macro cell and a Home-eNB 72-2that is a local node. The eNB 72-1 is equivalent to a large-scale basestation device and has a relatively large-scale coverage as the coveragein a range in which communication is allowed with the user equipment UE71. The Home-eNB 72-2 is equivalent to a small-scale base station deviceand has a relatively small-scale coverage as the coverage.

The eNB 72-1 is connected to an MME/S-GW unit (hereinafter, referred toas an “MME unit” in some cases) 73 including an MME, S-GW or MME andS-GW through an S1 interface, and control information is communicatedbetween the eNB 72-1 and the MME unit 73. A plurality of MME units 73may be connected to one eNB 72-1. The eNBs 72-1 are connected to eachother by means of an X2 interface, and control information iscommunicated between the eNBs 72-1.

The Home-eNB 72-2 is connected to the MME unit 73 by means of an S1interface, and control information is communicated between the Home-eNB72-2 and the MME unit 73. A plurality of Home-eNBs 72-2 are connected toone MME unit 73. Also, the Home-eNBs 72-2 are connected to the MME units73 through a Home-eNB Gateway (HeNBGW) 74. The Home-eNBs 72-2 areconnected to the HeNBGW 74 by means of the S1 interface, and the HeNBGW74 is connected to the MME units 73 through an S1 interface. One or aplurality of Home-eNBs 72-2 are connected to one HeNBGW 74, andinformation is communicated therebetween through an S1 interface. TheHeNBGW 74 is connected to one or a plurality of MME units 73, andinformation is communicated therebetween through an S1 interface.

Further, 3GPP is currently studying the configuration below. The X2interface between the Home-eNBs 72-2 is not supported. The HeNBGW 74appears to the MME unit 73 as the eNB 72-1. The HeNBGW 74 appears to theHome-eNB 72-2 as the MME unit 73. The interfaces between the Home-eNBs72-2 and the MME units 73 are the same, which are the S1 interfaces,irrespective of whether or not the Home-eNB 72-2 is connected to the MMEunit 73 through the HeNBGW 74. The mobility to the Home-eNB 72-2 or themobility from the Home-eNB 72-2 that spans the plurality of MME units 73is not supported. The Home-eNB 72-2 supports a single cell.

FIG. 8 is a block diagram showing the configuration of the userequipment (user equipment 71 of FIG. 7) according to the presentinvention. The transmission process of the user equipment 71 shown inFIG. 8 is described. First, a transmission data buffer unit 803 storesthe control data from a protocol processing unit 801 and the user datafrom an application unit 802. The data stored in the transmission databuffer unit 803 is transmitted to an encoding unit 804 and is subjectedto an encoding process such as error correction. There may exist thedata output from the transmission data buffer unit 803 directly to amodulating unit 805 without the encoding process. The data encoded bythe encoding unit 804 is modulated by the modulating unit 805. Themodulated data is output to a frequency converting unit 806 after beingconverted into a baseband signal, and then is converted into a radiotransmission frequency. After that, a transmission signal is transmittedfrom an antenna 807 to the base station 72.

The user equipment 71 executes the reception process as follows. Theradio signal is received through the antenna 807 from the base station72. The received signal is converted from a radio reception frequency toa baseband signal by the frequency converting unit 806 and is thendemodulated by a demodulating unit 808. The demodulated data istransmitted to a decoding unit 809 and is subjected to a decodingprocess such as error correction. Among the pieces of decoded data, thecontrol data is transmitted to the protocol processing unit 801, whilethe user data is transmitted to the application unit 802. A series ofprocesses of the user equipment 71 is controlled by a control unit 810.This means that, though not shown in FIG. 8, the control unit 810 isconnected to the respective units 801 to 809.

FIG. 9 is a block diagram showing the configuration of the base station(base station 72 of FIG. 7) according to the present invention. Thetransmission process of the base station 72 shown in FIG. 9 isdescribed. An EPC communication unit 901 performs datatransmission/reception between the base station 72 and the EPCs (such asMME unit 73 and HeNBGW 74). A communication with another base stationunit 902 performs data transmission/reception to/from another basestation. The X2 interface between the Home-eNBs 72-2 is not intended tobe supported, and accordingly, it is conceivable that the communicationwith another base station unit 902 may not exist in the Home-eNB 72-2.The EPC communication unit 901 and the communication with another basestation unit 902 respectively transmit/receive information to/from aprotocol processing unit 903. The control data from the protocolprocessing unit 903, and the user data and control data from the EPCcommunication unit 901 and the communication with another base stationunit 902 are stored in a transmission data buffer unit 904.

The data stored in the transmission data buffer unit 904 is transmittedto an encoding unit 905 and is then subjected to an encoding processsuch as error correction. There may exist the data output from thetransmission data buffer unit 904 directly to a modulating unit 906without the encoding process. The encoded data is modulated by themodulating unit 906. The modulated data is output to a frequencyconverting unit 907 after being converted into a baseband signal, and isthen converted into a radio transmission frequency. After that, atransmission signal is transmitted from an antenna 908 to one or aplurality of user equipments 71.

While, the reception process of the base station 72 is executed asfollows. A radio signal from one or a plurality of user equipments 71 isreceived through the antenna 908. The received signal is converted froma radio reception frequency into a baseband signal by the frequencyconverting unit 907, and is then demodulated by a demodulating unit 909.The demodulated data is transmitted to a decoding unit 910 and is thensubjected to a decoding process such as error correction. Among thepieces of decoded data, the control data is transmitted to the protocolprocessing unit 903, EPC communication unit 901, or communication withanother base station unit 902, while the user data is transmitted to theEPC communication unit 901 and the communication with another basestation unit 902. A series of processes by the base station 72 iscontrolled by a control unit 911. This means that, though not shown inFIG. 9, the control unit 911 is connected to the respective units 901 to910.

The functions of the Home-eNB 72-2 currently under discussion of 3GPPare described below (see Chapter 4.6.2 of Non-Patent Document 1). TheHome-eNB 72-2 has the same function as that of the eNB 72-1. Inaddition, the Home-eNB 72-2 has the function of discovering a suitableserving HeNBGW 74 in a case of connection to the HeNBGW 74. The Home-eNB72-2 is connected only to one HeNBGW 74. That is, in a case of theconnection to the HeNBGW 74, the Home-eNB 72-2 does not use the Flexfunction in the S1 interface. When the Home-eNB 72-2 is connected to oneHeNBGW 74, it is not simultaneously connected to another HeNBGW 74 oranother MME unit 73.

The TAC and PLMN ID of the Home-eNB 72-2 are supported by the HeNBGW 74.When the Home-eNB 72-2 is connected to the HeNBGW 74, selection of theMME unit 73 at “UE attachment” is performed by the HeNBGW 74 instead ofthe Home-eNB 72-2. The Home-eNB 72-2 may be deployed without networkplanning. In this case, the Home-eNB 72-2 is moved from one geographicalarea to another geographical area. Accordingly, the Home-eNB 72-2 inthis case is required to be connected to a different HeNBGW 74 dependingon its location.

FIG. 10 is a block diagram showing the configuration of the MMEaccording to the present invention. FIG. 10 shows the configuration ofan MME 73 a included in the MME unit 73 shown in FIG. 7 described above.A PDN GW communication unit 1001 performs data transmission/receptionbetween the MME 73 a and a PDN GW. A base station communication unit1002 performs data transmission/reception between the MME 73 a and thebase station 72 by means of the S1 interface. In the case where the datareceived from the PDN GW is user data, the user data is transmitted fromthe PDN GW communication unit 1001 to the base station communicationunit 1002 through a user plane communication unit 1003 and is thentransmitted to one or a plurality of base stations 72. In the case wherethe data received from the base station 72 is user data, the user datais transmitted from the base station communication unit 1002 to the PDNGW communication unit 1001 through the user plane communication unit1003 and is then transmitted to the PDN GW.

In the case where the data received from the PDN GW is control data, thecontrol data is transmitted from the PDN GW communication unit 1001 to acontrol plane control unit 1005. In the case where the data receivedfrom the base station 72 is control data, the control data istransmitted from the base station communication unit 1002 to the controlplane control unit 1005.

A HeNBGW communication unit 1004 is provided in the case where theHeNBGW 74 is provided, which performs data transmission/reception bymeans of the interface (IF) between the MME 73 a and the HeNBGW 74according to an information type. The control data received from theHeNBGW communication unit 1004 is transmitted from the HeNBGWcommunication unit 1004 to the control plane control unit 1005. Theprocessing results of the control plane control unit 1005 aretransmitted to the PDN GW through the PDN GW communication unit 1001.The processing results of the control plane control unit 1005 aretransmitted to one or a plurality of base stations 72 by means of the S1interface through the base station communication unit 1002, and aretransmitted to one or a plurality of HeNBGWs 74 through the HeNBGWcommunication unit 1004.

The control plane control unit 1005 includes an NAS security unit1005-1, an SAE bearer control unit 1005-2, and an idle state mobilitymanaging unit 1005-3, and performs overall process for the controlplane. The NAS security unit 1005-1 provides, for example, security of anon-access stratum (NAS) message. The SAE bearer control unit 1005-2manages, for example, a system architecture evolution (SAE) bearer. Theidle state mobility managing unit 1005-3 performs, for example, mobilitymanagement of an idle state (LTE-IDLE state, which is merely referred toas idle as well), generation and control of paging signal in an idlestate, addition, deletion, update, and search of a tracking area (TA) ofone or a plurality of user equipments 71 being served thereby, andtracking area list (TA list) management.

The MME 73 a begins a paging protocol by transmitting a paging messageto the cell belonging to a tracking area (TA) in which the UE isregistered. The idle state mobility managing unit 1005-3 may manage theCSG of the Home-eNBs 72-2 to be connected to the MME 73 a, CSG-IDs, anda whitelist.

In the CSG-ID management, the relationship between a user equipmentcorresponding to the CSG-ID and the CSG cell is managed (added, deleted,updated or searched). For example, it may be the relationship betweenone or a plurality of user equipments whose user access registration hasbeen performed with a CSG-ID and the CSG cells belonging to this CSG-ID.In the whitelist management, the relationship between the user equipmentand the CSG-ID is managed (added, deleted, updated, or searched). Forexample, one or a plurality of CSG-IDs with which user registration hasbeen performed by a user equipment may be stored in the whitelist. Theabove-mentioned management related to the CSG may be performed byanother part of the MME 73 a. A series of processes by the MME 73 a iscontrolled by a control unit 1006. This means that, though not shown inFIG. 10, the control unit 1006 is connected to the respective units 1001to 1005.

The function of the MME 73 a currently under discussion of 3GPP isdescribed below (see Chapter 4.6.2 of Non-Patent Document 1). The MME 73a performs access control for one or a plurality of user equipmentsbeing members of closed subscriber groups (CSGs). The MME 73 arecognizes the execution of paging optimization as an option.

FIG. 11 is a block diagram showing the configuration of the HeNBGW 74shown in FIG. 7 that is a HeNBGW according to the present invention. AnEPC communication unit 1101 performs data transmission/reception betweenthe HeNBGW 74 and the MME 73 a by means of the S1 interface. A basestation communication unit 1102 performs data transmission/receptionbetween the HeNBGW 74 and the Home-eNB 72-2 by means of the S1interface. A location processing unit 1103 performs the process oftransmitting, to a plurality of Home-eNBs 72-2, the registrationinformation or the like among the data transmitted from the MME 73 athrough the EPC communication unit 1101. The data processed by thelocation processing unit 1103 is transmitted to the base stationcommunication unit 1102 and is transmitted to one or a plurality ofHome-eNBs 72-2 through the S1 interface.

The data only caused to pass through (to be transparent) withoutrequiring the process by the location processing unit 1103 is passedfrom the EPC communication unit 1101 to the base station communicationunit 1102, and is transmitted to one or a plurality of Home-eNBs 72-2through the S1 interface. A series of processes by the HeNBGW 74 iscontrolled by a control unit 1104. This means that, though not shown inFIG. 11, the control unit 1104 is connected to the respective units 1101to 1103.

The function of the HeNBGW 74 currently under discussion of 3GPP isdescribed below (see Chapter 4.6.2 of Non-Patent Document 1). The HeNBGW74 relays an S1 application. The HeNBGW 74 terminates the S1 applicationthat is not associated with the user equipment 71 though it is a part ofthe procedures toward the Home-eNB 72-2 and towards the MME 73 a. Whenthe HeNBGW 74 is deployed, the procedure that is not associated with theuser equipment 71 is communicated between the Home-eNB 72-2 and theHeNBGW 74 and between the HeNBGW 74 and the MME 73 a. The X2 interfaceis not set between the HeNBGW 74 and another node. The HeNBGW 74recognizes the execution of paging optimization as an option.

Next, an example of a typical cell search method in a mobilecommunication system is described. FIG. 12 is a flowchart showing anoutline from cell search to idle state operation performed by a userequipment (UE) in the LTE communication system. When starting cellsearch, in Step ST1201, the user equipment synchronizes the slot timingand frame timing by a primary synchronization signal (P-SS) and asecondary synchronization signal (S-SS) transmitted from a neighbourbase station. Synchronization codes, which correspond to physical cellidentities (PCIs) assigned per cell one by one, are assigned to thesynchronization signals (SS) including the P-SS and S-SS. The number ofPCIs is currently studied in 504 ways, and these 504 ways are used forsynchronization, and the PCIs of the synchronized cells are detected(specified).

Next, in Step ST1202, the user equipment detects a reference signal RS(cell-specific reference signal (CRS)) transmitted from the base stationper cell and measures the received power (also referred to as RSRP). Thecode corresponding to the PCI one by one is used for the referencesignal RS, and separation from another cell is enabled by correlationusing the code. The code for RS of the cell is derived from the PCIspecified in Step ST1201, which makes it possible to detect the RS andmeasure the RS received power.

Next, in Step ST1203, the user equipment selects the cell having thebest RS reception quality (for example, cell having the highest RSreceived power, that is, best cell) from one or more cells that havebeen detected up to Step ST1202.

In Step ST1204, next, the user equipment receives the PBCH of the bestcell and obtains the BCCH that is the broadcast information. A masterinformation block (MIB) containing the cell configuration information ismapped to the BCCH over the PBCH. Accordingly, the MIB is obtained byobtaining the BCCH through reception of the PBCH. Examples of the MIBinformation include the downlink (DL) system bandwidth (also referred toas transmission bandwidth configuration (dl-bandwidth)), transmissionantenna number, and system frame number (SFN).

In Step ST1205, next, the user equipment receives the DL-SCH of the cellbased on the cell configuration information of the MIB, to therebyobtain a system information block (SIB) 1 of the broadcast informationBCCH. The SIB1 contains the information related to the access to thecell, information related to cell selection, and scheduling informationof other SIB (SIBk; k is an integer equal to or larger than two). Inaddition, the SIB1 contains a tracking area code (TAC).

In Step ST1206, next, the user equipment compares the TAC of the SIB1received in Step ST1205 with the TAC in the tracking area (TA) list thathas been already possessed by the user equipment. In a case where theTAC received in Step ST1205 is identical to the TAC included in the TAlist as a result of the comparison, the user equipment enters an idlestate operation in the cell. In a case where the TAC received in StepST1205 is not included in the TA list as a result of the comparison, theuser equipment requires a core network (EPC) (including MME and thelike) to change a TA through the cell for performing tracking areaupdate (TAU). The core network updates the TA list based on anidentification number (such as a UE-ID) of the user equipmenttransmitted from the user equipment together with a TAU request signal.The core network transmits the updated TA list to the user equipment.The user equipment rewrites (updates) the TAC list of the user equipmentwith the received TA list. After that, the user equipment enters theidle state operation in the cell.

In the LTE and universal mobile telecommunication system (UMTS), theintroduction of a closed subscriber group (CSG) cell is studied. Asdescribed above, access is allowed for only one or a plurality of userequipments registered with the CSG cell. A CSG cell and one or aplurality of user equipments registered with the CSG cell constitute oneCSG. A specific identification number referred to as CSG-ID is added tothe thus constituted CSG. Note that one CSG may contain a plurality ofCSG cells. After being registered with any one of the CSG cells, theuser equipment can access another CSG cell of the CSG to which theregistered CSG cell belongs.

Alternatively, the Home-eNB in the LTE or the Home-NB in the UMTS isused as the CSG cell in some cases. The user equipment registered withthe CSG cell has a whitelist. Specifically, the whitelist is stored inthe subscriber identity module (SIM)/USIM. The CSG information of theCSG cell with which the user equipment has been registered is stored inthe whitelist. Specific examples of the CSG information include CSG-ID,tracking area identity (TAI) and TAC. Any one of the CSG-ID and TAC isadequate as long as they are associated with each other. Alternatively,GCI is adequate as long as the CSG-ID and TAC are associated with globalcell identity (GCI).

As can be seen from the above, the user equipment that does not have awhitelist (including a case where the whitelist is empty in the presentinvention) is not allowed to access the CSG cell but is allowed toaccess the non-CSG cell only. On the other hand, the user equipmentwhich has a whitelist is allowed to access the CSG cell of the CSG-IDwith which registration has been performed as well as the non-CSG cell.

3GPP is discussing that all physical cell identities (PCIs) are split(referred to as PCI-split) into ones reserved for CSG cells and theothers reserved for non-CSG cells (see Non-Patent Document 5). Further,3GPP is discussing that the PCI split information is broadcast in thesystem information from the base station to the user equipments beingserved thereby. Non-Patent Document 5 discloses the basic operation of auser equipment by PCI split. The user equipment that does not have thePCI split information needs to perform cell search using all PCIs (forexample, using all 504 codes). On the other hand, the user equipmentthat has the PCI split information is capable of performing cell searchusing the PCI split information.

Further, 3GPP has determined that the PCIs for hybrid cells are notcontained in the PCI range for CSG cells (see Chapter 10.7 of Non-PatentDocument 1).

In 3GPP, there are two modes in the method of selecting or reselecting aCSG cell by a user equipment. One is an automatic mode. The feature ofthe automatic mode is described below. The user equipment performsselection or reselection with the use of an allowed CSG list (allowedCSG ID list) in the user equipment. After the completion of PLMNselection, the user equipment camps on one cell in the selected PLMNonly in a case of a non-CSG cell or a CSG cell with a CSG ID present inthe allowed CSG list. The user equipment disables an autonomous searchfunction of the CSG cell if the allowed CSG list of the user equipmentis empty (see Chapter 5.2.4.8.1 of Non-Patent Document 3).

The second is a manual mode. The feature of the manual mode is describedbelow. The user equipment shows a list of available CSGs in thecurrently selected PLMN to a user. The list of CSGs provided to the userby the user equipment is not limited to the CSGs included in the allowedCSG list stored in the user equipment. The user selects the CSG based onthe list of CSGs, and then the user equipment camps on the cell with theselected CSG ID, to thereby attempt registration (see Chapter 5.2.4.8.1of Non-Patent Document 3).

The HeNB and HNB are required to support various services. For example,an operator causes the predetermined HeNB and HNB to register userequipments therein and permits only the registered user equipments toaccess the cells of the HeNB and HNB, which increases radio resourcesavailable for the user equipments and enables high-speed communication.In such a service, the operator correspondingly sets a higher accountingfee compared with a normal service.

In order to achieve the above-mentioned service, the closed subscribergroup cell (CSG cell) accessible only to the registered (subscribed ormember) user equipments is introduced. It is required to install a largenumber of closed subscriber group cells (CSG cells) in shopping malls,apartment buildings, schools, companies and the like. For example, thefollowing manner of use is required; the CSG cells are installed foreach store in shopping malls, for each room in apartment buildings, foreach classroom in schools, and for each section in companies such thatonly the users who have registered with the respective CSG cells arepermitted to use those CSG cells. The HeNB/HNB is required not only tocomplement the communication outside the coverage of the macro cell butalso to support various services as described above. This also leads toa case where the HeNB/HNB is installed within the coverage of the macrocell.

3GPP is pursuing the study of the MTC technique (see Non-Patent Document8). The MTC is machine to machine (M2M) communication, which differsfrom the conventional human to human (H2H) communication. In otherwords, the MTC does not require human interaction, that is, interactionbetween humans. Examples of applications of the service using the MTCtechnique (hereinafter, referred to as “MTC service”) include meteringof gas, power and water, and fleet management and order management(tracking and tracing). The MTC service is characterized by a largenumber of devices for MTC (MTC devices: MTCDs). As one example, 30,000or more MTCDs are assumed to be served by one cell.

3GPP is studying the architecture of the MTC (see 3GPP R3-100315(hereinafter, referred to as “Non-Patent Document 10”)). FIG. 13 is adiagram illustrating an example of the architecture of the MTC, which isstudied by 3GPP. The support of MTC service is studied not only in theLTE communication system but also in the WCDMA communication system.

With reference to FIG. 13, MTCDs 1301 to 1304 and an NB/eNB 1305 areconnected by means of interfaces Uu 1311 to 1314, respectively. Aserving GPRS support node/mobility management entity (SGSN/MME) 1306 isconnected to the NB/eNB 1305 by means of an IuPS/S1 interface 1315.Though not shown here, a radio network controller (RNC) is locatedbetween the NB and the SGSN. The NB and the RNC are connected by meansof an Iub interface, and the RNC is connected to the SGSN by means of anIuPS interface.

A home location register/home subscriber server (HLR/HSS) 1307 isconnected to the SGSN/MME 1306 by means of a Gr/S6a interface 1316. Acommunication operator domain 1317 includes the NB/eNB 1305, SGSN/MME1306, HLR/HSS 1307, and the like.

An MTC server 1308 is included in the communication operator domain1317. An MTC user 1309 that performs MTC service is connected to the MTCserver 1308 by means of an application program interface (API) 1310.3GPP is currently studying a node in the communication operator domain1317, to which the MTC server 1308 is connected.

The information for MTC service is notified by the MTC user 1309 fromthe MTC server 1308 to the MTCDs 1301 to 1304 with the use of the NB/eNB1305, SGSN/MME 1306, and HLR/HSS 1307 that are nodes in thecommunication operator domain 1317. In contrast, the information fromthe MTCDs 1301 to 1304 is notified to the MTC server 1308 with the useof the NB/eNB 1305, SGSN/MME 1306, and HLR/HSS 1307 that are nodes inthe communication operator domain 1317, and the MTC user 1309 uses theinformation.

In the MTC service, there occurs a situation in which data iscommunicated from a large number of MTCDs or to a large number of MTCDsat the same time. The situation described above occurs in a case where,for example, metering data is transmitted from the MTCD to the MTCserver at one o'clock in the morning once a day or in a case where theMTC server requests the MTCD to transmit the metering data. Anotherexample is the case where, for example, data for upgrading software istransmitted to the all MTCDs simultaneously.

The conventional communication system is optimized for H2Hcommunication, and thus, no measure is taken against a situation inwhich a large number of MTCDs communicate data at the same time. Asituation in which data is communicated from a large number of MTCDs orto a large number of MTCDs at the same time causes a problem that aradio network and a core network become congested. In other words, aproblem that those networks are overloaded arises.

For example, in a case where an MTC server requests a large number ofMTCDs to transmit metering data simultaneously, the MTCDs 1301 to 1304transmit many pieces of data to the MTC server 1308 with the use of theNB/eNB 1305, SGSN/MME 1306, and HLR/HSS 1307 that are nodes in thecommunication operator domain 1317. In such a situation, an overloadedstate is caused in the communication between the NB/eNB 1305 and theSGSN/MME 1306. This causes a problem of a shortage of communicationresources or an occurrence of an overloaded state in the processes bythe NB/eNB 1305 and the SGSN/MME 1306.

Non-Patent Document 9 mentioned above discloses the following solutionto the problem of the congested state occurring in the core network. AneNB holds back and aggregates signaling messages common to MTCDs of thesame group, so that the signaling messages are compacted. Specifically,Non-Patent Document 9 describes the method in which an eNB holds backthe NAS signaling messages from MTCDs for a pre-defined timeout or tilla number of non-access stratum (NAS) signaling messages arrive. However,Non-Patent Document 9 does not suggest a problem in a case where a largenumber of MTCD groups to be served by an eNB are located, and does notdisclose a solution to the problem as well. In addition, Non-PatentDocument 9 does not disclose the method in which an eNB holds back andaggregates signaling messages from MTCDs, and then transmits those to acore network side.

S2-101008 (hereinafter, referred to as “Non-Patent Document 11”) by 3GPPdiscloses the following solution to a problem of the congested stateoccurring in the core network. It is described that MTCDs in the sameMTCD group share one network resource allocated to a UE that is not anMTCD. However, Non-Patent Document 11 does not suggest a problem in acase where a large number of MTCD groups to be served by an eNB arelocated and does not disclose a solution as well. Further, Non-PatentDocument 11 discloses that an international mobile subscriber identity(IMSI), an MTCD number, and a cell number as source addresses are mappedto a message from an MTCD to an MTC server. However, Non-Patent Document11 does not disclose the method of sharing one network resource amongMTCDs of the same MTCD group.

R2-103269 (hereinafter, referred to as “Non-Patent Document 12”) by 3GPPdescribes a problem that in a case where, for example, the MTCDs areinstalled in the basement, the channel quality between individual MTCDand eNB is too low such that the direct communication therebetween isnot practical. In order to tackle such a problem, Non-Patent Document 12discloses to install a concentrator between an eNB and an MTCD,separately from the eNB. However, Non-Patent Document 12 does notdisclose the transmission method from a concentrator to an eNB.

A problem to be solved in the first embodiment is described below. In acase where a large number of MTCD groups to be served by an eNB arelocated, signaling messages cannot be reduced by the above-mentionedmethod disclosed in Non-Patent Document 9, that is, the method in whichan eNB holds back and aggregates signaling messages common to MTCDs ofthe same MTCD group. The first embodiment discloses a communicationsystem capable of mitigating, even if a large number of MTCD groups tobe served by an eNB are located, the congestion of a core network in asituation in which the pieces of data from a large number of MTCDs needto be communicated. The communication system of the present embodimentis a mobile communication system. The MTCD group is equivalent to aterminal device group.

A solution in the first embodiment is described below. A HeNB performs aconcentration process of concentrating the data from MTCDs being servedthereby to an MME, SGSN, or MTC server being a core network. The HeNBdoes not transmit, relay, or transmit therethrough the data from MTCDsbeing served thereby to the MME, SGSN, or MTC server being a corenetwork per se but concentrates the data. This enables the concentrationprocess even in a case where a large number of MTCDs belonging todifferent MTCD groups to be served by a HeNB are located. Accordingly,it is possible to mitigate congestion in a core network even in asituation in which a large number of MTCDs belonging to different MTCDgroups to be served by a HeNB are located.

In a case where a HeNB operates in a closed access mode or hybrid accessmode, the data from MTCDs belonging to the same CSG to a core networkmay be concentrated. This allows a HeNB to process only the data fromthe MTCDs registered with the same CSG to that of the own HeNB amongMTCDs being served thereby, which enables a process according to theclosed access mode such that the HeNB operates as a cell that can beaccessed by only the CSG members.

In a case where a HeNB operates in a hybrid access mode, user equipmentsother than MTCDs may use the open access mode and MTCDs may use theclosed access mode. The MTCDs may be allowed to access only the HeNBs ofthe same CSG. In this case, a HeNB may concentrate the data fromcommunication terminals that make access in the closed access mode to acore network.

The same effects can be achieved if an eNB performs the processperformed by a HeNB. The following description is mainly given of a HeNBfor the sake of convenience.

The following two (1) and (2) are disclosed as specific examples of thecommunication method between a HeNB and an MTCD; (1) communicationmethod in a mobile communication system standardized by 3GPP, and (2)communication method in a system other than the mobile communicationsystem standardized by 3GPP.

The following five (1) to (5) are disclosed as specific examples of thecommunication method in a system other than the mobile communicationsystem standardized by 3GPP; (1) infrared communication, (2) coaxialcable communication, (3) optical fiber communication, (4) Bluetooth(registered trademark) communication, and (5) ZigBee (registeredtrademark) communication.

Specific examples of the data from an MTCD to a core network, which is atarget of the concentration process by a HeNB, are disclosed below.First, the following two (1) and (2) are disclosed as specific examplesof the contents of the data which is a target of the concentrationprocess; (1) control data, and (2) user data. Next, the following two(1) and (2) are disclosed as specific examples of the signaling which isa target of the concentration process; (1) NAS signaling or NAS message,and (2) RRC signaling or RRC message.

The following three (1) to (3) are disclosed as specific examples of themethod in which a HeNB distinguishes whether a user equipment (UE) beingserved thereby is an MTCD or not an MTCD. A user equipment (UE) that isnot an MTCD is also referred to as “normal UE” in the followingdescription.

(1) Identities of different systems are used in an MTCD and a normal UE.For example, an MTCD-ID is newly provided separately from the currentUE-ID. The current UE-ID may be an identity for normal UE and an MTCD-IDmay be an identity for MTCD.

(2) An indicator for distinguishing whether or not a UE is an MTCD(hereinafter, also referred to as “MTCD indicator”) is newly provided.The following seven (a) to (g) are disclosed as specific examples of theMTCD indicator; (a) indicator indicating whether a UE is an MTCD ornormal UE, (b) indicator indicating whether or not a UE is an MTCD,where if the indicator indicating that a UE is not an MTCD is included,a HeNB judges the UE as a normal UE, (c) indicator indicating whether ornot a UE is a normal UE, where if the indicator indicating that a UE isnot a normal UE is included, a HeNB judges the UE as an MTCD, (d)indicator indicating that a UE is an MTCD, where if the indicatorindicating that a UE is an MTCD is not included, a HeNB judges the UE asa normal UE, (e) indicator indicating that a UE is not an MTCD, where ifthe indicator indicating that a UE is not an MTCD is not included, aHeNB judges the UE as an MTCD, (f) indicator indicating that a UE is anormal UE, where if the indicator indicating that a UE is a normal UE isnot included, a HeNB judges the UE as an MTCD, and (g) indicatorindicating that a UE is not a normal UE, where if the indicatorindicating that a UE is not a normal UE is included, a HeNB judges theUE as a normal UE.

(3) A HeNB makes judgment based on whether or not access has been madeby a communication method in a system other than the mobilecommunication system standardized by 3GPP. The user equipment that hasmade access by the communication method in a system other than themobile communication system standardized by 3GPP is judged as an MTCD.

Among the above-mentioned specific examples of the method in which aHeNB distinguishes whether a user equipment (UE) being served thereby isan MTCD or not an MTCD, in the specific example (1), specific example(2)-(d), specific example (2)-(g), and specific example (3), a parameteror process is not required to be newly added if the current UE is anormal UE. Therefore, the use of the specific example (1), specificexample (2)-(d), specific example (2)-(g), or specific example (3)enables to solve the problem without changing the current specificationsof the UE.

The following two (1) and (2) are disclosed as specific examples of themethod of notifying a HeNB of the distinction whether a UE is an MTCD ornot an MTCD. (1) A HeNB is notified of the distinction whether the UE isan MTCD or not an MTCD with the use of an RRC message or RRC signaling.An identity in the different system is used for the RRC message or RRCsignaling. Alternatively, an MTCD indicator is mapped to the RRC messageor RRC signaling. Specific examples of the RRC signaling include “RRCConnection Request” (see Non-Patent Document 2). Contrary to thespecific example (2) below, in the specific example (1), a HeNB canjudge whether or not a UE is an MTCD before receiving the data to a corenetwork, which is a target of the concentration process. This enables toprevent a control delay in the concentration process by a HeNB.

(2) A HeNB is notified of the distinction whether the UE is an MTCD ornot an MTCD with the use of the data to the core network, on which theconcentration process is performed. An identity in the different systemis used for the data to the core network. An MTCD indicator is mapped tothe data to the core network. The identity in the different system maybe used for a header/footer of the data to the core network.Alternatively, an MTCD indicator may be mapped to a header/footer of thedata to the core network. If distinction can be made whether the UE isan MTCD or not an MTCD with the use of the header/footer of the data tothe core network, a HeNB does not need to always interpret the contentsof the message from the MTCD to the core network. Therefore, theprocessing load of the HeNB can be reduced.

The following four (1) to (4) are disclosed as specific examples of theconcentration process. (1) The NAS signaling or NAS message isterminated, and an MME is notified of this separately. On this occasion,an MME may be notified of the above from which unnecessary data isreduced. This reduces the traffic from the HeNB to the core network, andthus the congestion of the core network can be mitigated. (2) The NASsignaling or NAS message is interpreted, and an MME is notified of thisseparately. On this occasion, an MME may be notified of the above fromwhich unnecessary data is reduced. This reduces the traffic from theHeNB to the core network, and thus the congestion of the core networkcan be mitigated. (3) An MME is collectively notified of the pieces ofdata from one or a plurality of MTCDs to a core network. This reducesthe number of communication times from a HeNB to a core network, and thecongestion of the core network can be mitigated. (4) The combination of(1) to (3) above.

The concept that a HeNB terminates NAS signaling is described withreference to FIG. 14 and FIG. 15. First, a protocol stack of controldata between a UE and an MME in a conventional technique is describedwith reference to FIG. 14. FIG. 14 is a diagram showing a protocol stackof control data between a UE and an MME in a conventional technique. Theinterface between the UE and HeNB is defined as LTE-Uu 1401 (seeNon-Patent Document 1 and TS23.401 V10.0.0 (hereinafter, referred to as“Non-Patent Document 13”) by 3GPP). The interface between the HeNB andMME is defined as S1-MME 1402 (see Non-Patent Document 13).

The UE, HeNB, and MME have layer 1 (L1) protocols 1403-1, 1403-2 and1403-3, and 1403-4, respectively. The UE and HeNB have medium accesscontrol (MAC) protocols 1404-1 and 1404-2, respectively. The HeNB andMME have layer 2 (L2) protocols 1405-1 and 1405-2, respectively. The UEand HeNB have radio link control (RLC) protocols 1406-1 and 1406-2,respectively. The HeNB and MME have internet protocols (IPs) 1407-1 and1407-2, respectively. The UE and HeNB have packet data convergenceprotocols (PDCPs) 1408-1 and 1408-2, respectively. The HeNB and MME havestream control transport protocols for the control plane (SCTPs) 1409-1and 1409-2, respectively. The UE and HeNB have radio resource control(RRC) protocols 1410-1 and 1410-2, respectively. The HeNB and MME haveS1 application protocols (S1-APs) 1411-1 and 1411-2, respectively.

A relay 1412 is performed in each protocol layer within the HeNB. The UEand MME have non-access stratum (NAS) protocols 1413-1 and 1413-2,respectively. The NAS protocol supports mobility managementfunctionality and user plane bearer activation, modification, anddeactivation.

Next, a protocol stack of control data between an MTCD and an MME in thefirst embodiment is described with reference to FIG. 15. FIG. 15 is adiagram showing the protocol stack of control data between the MTCD andMME in the first embodiment. The portions of FIG. 15 corresponding tothe protocol layers shown in FIG. 14 are denoted by the same referencesymbols, and the common description is not given here.

The interface between the MTCD and HeNB is defined as LTE-Uu 1401. TheMTCD has the layer 1 (L1) protocol 1403-1, MAC protocol 1404-1, RLCprotocol 1406-1, PDCP 1408-1 and RRC protocol 1410-1, and an NASprotocol for MTC 1501-1. Herein, though the NAS protocol for MTC doesnot reach the MME, the term “NAS” is used for the sake of convenience.

The HeNB has the layer 1 (L1) protocol 1403-2, MAC protocol 1404-2, RLCprotocol 1406-2, PDCP 1408-2 and RRC protocol 1410-2, and an NASprotocol for MTC 1501-2. Due to the existence of the NAS protocol forMTC 1501-2 in the HeNB, the HeNB can perform concentration 1504described above. The relay 1412 is performed in each protocol layerwithin the HeNB. The HeNB and MME have S1-AP 1502-1, 1502-2 and 1502-3,respectively. While FIG. 15 shows the S1-APs in the HeNB throughseparation into the S1-AP 1502-1 and S1-AP 1502-3, one S1-AP may beprovided in the HeNB. The MME has an NAS protocol for normal UE 1503.

The protocol stack of control data between the normal UE and MME in thefirst embodiment is similar to that of the conventional technique, whichis not described here (see FIG. 14). Note that the MME has the NASprotocol for normal UE 1503 (see FIG. 15).

Next, a specific operation example using the first embodiment isdescribed with reference to FIG. 16 and FIG. 17. In this operationexample, a case of NAS signaling is disclosed as a specific example ofthe data from an MTCD to a core network, which is a target of theconcentration process by a HeNB. Further, a case in which an MTCDindicator is mapped to the RRC message “RRC Connection Request” isdisclosed as a specific example of the method in which a HeNBdistinguishes whether a user equipment (UE) being served thereby is anMTCD or not an MTCD. Further, a case in which an MME is collectivelynotified of pieces of data from one or a plurality of MTCDs to a corenetwork is disclosed as a specific example of the concentration process.

First, a specific example of the concentration process by a HeNB in thefirst embodiment is described with reference to FIG. 16. FIG. 16 is aflowchart showing the procedure by a HeNB regarding the concentrationprocess in the first embodiment.

In Step ST1601, the HeNB judges whether or not to have received the RRCmessage “RRC Connection Request” from a UE. In a case of judging to havereceived the RRC message from the UE, the HeNB moves to Step ST1602. Ina case of judging to not have received the RRC message from the UE, theHeNB repeats the judgment process of Step ST1601.

In Step ST1602, the HeNB checks an MTCD indicator to be mapped to theRRC message received in Step ST1601 and moves to Step ST1603.

In Step ST1603, the HeNB judges whether or not to have received the RRCmessage from the MTCD, that is, whether or not the UE that hastransmitted the RRC message received in Step ST1601 is an MTCD, based onthe MTCD indicator checked in Step ST1602. In a case of judging to havereceived the RRC message from the MTCD, that is, judging that the UEthat has transmitted the RRC message is an MTCD, the HeNB moves to StepST1604. In a case of judging to not have received the RRC message fromthe MTCD, that is, judging that the UE that has transmitted the RRCmessage is not an MTCD, the HeNB moves to Step ST1605.

In Step ST1604, the HeNB perform the concentrate process on the datafrom the MTCD to the core network. After ending the process of StepST1604, the HeNB ends the all procedure. In Step ST1605, the HeNB doesnot perform the concentrate process on the data from the UE to the corenetwork. In other words, the data is transmitted from the UE to the corenetwork via the HeNB. After ending the process of Step ST1605, the HeNBends the all procedure.

Next, a specific example of a sequence of the mobile communicationsystem in the first embodiment is described with reference to FIG. 17.FIG. 17 is a diagram showing the sequence of the mobile communicationsystem in the first embodiment. The HeNB has m normal UEs and n MTCDsbeing served thereby. Here, each of m and n each represents a naturalnumber. Normal UE_1 to normal UE_m represent m normal UEs, and MTCD_1 toMTCD_n represent n MTCDs.

In Step ST1701, the normal UE_1 transmits “RRC Connection Request” beingan RRC message, which contains an MTCD indicator, to the HeNB. In StepST1702, the normal UE_m transmits “RRC Connection Request” being an RRCmessage, which contains an MTCD indicator, to the HeNB. As describedabove, in the present embodiment, the normal UE_1 and normal UE_m amongthe normal UE_1 to normal UE_m transmit “RRC Connection Request” beingan RRC message containing an MTCD indicator to the HeNB assuming thatthe transmission data to the core network has occurred.

In Step ST1703, the MTCD_1 transmits “RRC Connection Request” being anRRC message, which contains an MTCD indicator, to the HeNB. In StepST1704, the MTCD_n transmits “RRC Connection Request” being an RRCmessage, which contains an MTCD indicator, to the HeNB. As describedabove, in the present embodiment, the MTCD_1 and MTCD_n among the MTCD_1to MTCD_n transmit “RRC Connection Request” being an RRC message, whichcontains an MTCD indicator, to the HeNB assuming that the transmissiondata to the core network has occurred.

In Step ST1705, the HeNB checks the MTCD indicator contained in “RRCConnection Request” and judges whether or not the RRC message is thedata from the MTCD. In a case of judging that the RRC message is thedata from the MTCD, the HeNB moves to Step ST1707. In a case of judgingthat the RRC message is not the data from the MTCD, the HeNB moves toStep ST1706.

In this operation example, Step ST1701 is the process of transmittingthe RRC message from the normal UE_1, and thus, the HeNB judges that theRRC message is not the data from the MTCD in Step ST1705 and moves toStep ST1706. Step ST1702 is the process of transmitting the RRC messagefrom the normal UE_m, and the HeNB judges that the RRC message is notthe data from the MTCD in Step ST1705 and moves to Step ST1706. StepST1703 is the process of transmitting the RRC message from the MTCD_1,and accordingly, the HeNB judges that the RRC message is the data fromthe MTCD in Step ST1705 and moves to Step ST1707. Step ST1704 is theprocess of transmitting the RRC message from the MTCD_n, andaccordingly, the HeNB judges that the RRC message is the data from theMTCD in Step ST1705 and moves to Step ST1707.

In Step ST1706, the HeNB is configured not to perform the concentrationprocess on the data from the normal UE being a user equipment (UE) otherthan the MTCD being served thereby to the core network. In thisoperation example, as to the UE other than the MTCD being servedthereby, the HeNB is configured not to perform the concentration processon NAS signaling from a UE, specifically, is configured not to performconcentration process on NAS signaling from a normal UE to a corenetwork.

The HeNB is configured to perform the concentration process on the datafrom an MTCD being served thereby to the core network In Step ST1707. Inthis operation example, the HeNB is configured to, as to an MTCD amongUEs being served thereby, perform the concentration process on the NASsignaling from the UE, specifically, is configured to perform theconcentration process on the NAS signaling from the MTCD to the corenetwork.

In Step ST1708, the normal UE_1 transmits, to the MME via the HeNB, NASsignaling being the data to the core network. The HeNB is configured notto perform the concentration process on NAS signaling from the normalUE_1 in Step ST1706, and thus, the MME is notified of the NAS signalingtransmitted from the normal UE_1 per se via the HeNB.

In Step ST1709, the normal UE_m transmits, to the MME via the HeNB, NASsignaling being the data to the core network. The HeNB is configured notto perform the concentration process on NAS signaling from the normalUE_m in Step ST1706, and thus, the MME is notified of the NAS signalingtransmitted from the normal UE_m per se via the HeNB. Similarly, in acase where NAS signaling is transmitted from another normal UE to theMME via the HeNB, the MME is notified of the NAS signaling transmittedfrom the another normal UE per se via the HeNB.

In Step ST1710, the MTCD_1 transmits, to the MME, NAS signaling beingthe data to the core network. The HeNB is configured to perform theconcentration process on the NAS signaling from the MTCD_1 in StepST1707, and thus, the concentration process is performed on the NASsignaling transmitted from the MTCD_1 in Step ST1712. Alternatively, thenormal process in a case where the HeNB receives “RRC ConnectionRequest” (see Non-Patent Document 2) may be omitted in Step ST1712 orStep ST1707. Alternatively, in Step ST1712, the HeNB may notify the MTCDthat has transmitted “RRC Connection Request” of “RRC Connectionreject”. The information indicating that the data from the MTCD to thecore network has been received may be mapped to “RRC Connection reject”.The information for requesting the retransmission of the data from theMTCD to the core network may be mapped to “RRC Connection reject”.

In Step ST1711, the MTCD_n transmits, to the MME, the NAS signalingbeing the data to the core network. The HeNB is configured to performthe concentration process on the NAS signaling from the MTCD_n in StepST1707, and thus, in Step ST1712, the concentration process is performedon the NAS signaling transmitted from the MTCD_n. Similarly, in a casewhere NAS signaling is transmitted from another MTCD to the MME, in StepST1712, the concentration process is performed on the NAS signalingtransmitted from the another MTCD.

In Step ST1712, the HeNB performs the concentration process on the NASsignaling being the data from an MTCD being served thereby to the corenetwork. In Step ST1713, the HeNB collects pieces of data to the MMEbeing pieces of data from the MTCD_1 and MTCD_n to the core network, andnotifies the MME of the collected pieces of data.

The first embodiment can achieve the following effects. According to thefirst embodiment, the HeNB performs the concentration process ofconcentrating pieces of data from MTCDs being served thereby to the corenetwork. In this case, the HeNB performs the concentration process overthe MTCD group. In other words, the HeNB performs the concentrationprocess regardless of an MTCD group, and thus, the number ofcommunication times from a HeNB to a core network or an amount of datacan be reduced even in a case where a large number of MTCD groups to beserved by the HeNB are located. Accordingly, even in a case where alarge number of MTCD groups to be served by a HeNB are located and asituation in which the large number of MTCDs need to communicate dataoccurs, a mobile communication system capable of mitigating thecongestion in a core network can be obtained.

Also in a case where an MTCD is set in a poor radio environment for amobile communication system standardized by 3GPP, an entity does notneed to be provided separately as a concentrator described in Non-PatentDocument 12, which enables communication with an MTC user and an MTCserver with the use of a 3GPP network starting from a HeNB. This isadvantageous in that a mobile communication system can be prevented frombecoming complicated because it is not required to separately provide anentity.

First Modification of First Embodiment

In a case where the first embodiment described above is used, thefollowing problem occurs. Contrary to the case in which theconcentration process is not performed, a delay occurs in datatransmission from an MTCD to a core network due to the concentrationprocess performed. A specific example in which a delay occurs isdescribed with reference to FIG. 17 described above.

The MME is notified of the NAS signaling from the normal UE_1 to thecore network, on which the concentration process is not performed, perse via the HeNB in Step ST1708. Meanwhile, the concentration process isperformed on the NAS signaling from the MTCD_1 to the core network, onwhich the concentration process is performed, in the HeNB in StepST1712, and then, the HeNB separately notifies the MME of the NASsignaling in Step ST1713. As described above, a control delay occurs inthe HeNB when the concentration process is performed.

Although it is typically considered that MTCDs are tolerant of delays inmany cases, MTCDs sensitive to delay occurrence are conceivable as well.Specific examples thereof include an MTCD equipped with a function ofdetecting an occurrence of an earthquake. The occurrence of delay in theabove-mentioned MTCD sensitive to delay occurrence with the use of thefirst embodiment above poses a problem in MTCD service.

A solution in a first modification of the first embodiment is describedbelow. A portion different from the solution in the first embodiment ismainly described. The portion that is not described here is as in thefirst embodiment.

A HeNB concentrates data from an MTCD tolerant of delays among MTCDsbeing served thereby to an MME, SGSN, MTC server, or the like being acore network. The HeNB does not concentrate data from an MTCD sensitiveto delays among MTCDs being served thereby to an MME, SGSN, MTC server,or the like being a core network.

The HeNB concentrates data from an MTCD having a low priority (lowpriority MTCD) among MTCDs being served thereby to an MME, SGSN, MTCserver, or the like being a core network. The HeNB does not concentratedata from an MTCD having a high priority (high priority MTCD) amongMTCDs being served thereby to an MME, SGSN, MTC server, or the likebeing a core network.

Disclosed below is a specific example of the method in which a HeNBdistinguishes whether or not a user equipment (UE) being served therebyis a low priority MTCD. An indicator indicating a priority (hereinafter,also referred to as “priority indicator”) is newly provided.

The following seven (a) to (g) are disclosed as specific examples of thepriority indicator.

(a) An indicator indicating whether a priority is high or low.

(b) An indicator indicating whether or not a priority is low. If anindicator indicating that the priority is not low, the HeNB judges thatthe MTCD has a high priority.

(c) An indicator indicating whether or not a priority is high. If anindicator indicating that the priority is not high, the HeNB judges thatthe MTCD has a low priority.

(d) An indicator indicating that an MTCD is a low priority MTCD. If anindicator indicating that a low priority MTC is not included, the HeNBjudges that the MTCD is a high priority MTCD.

(e) An indicator indicating that an MTCD is not a low priority MTCD. Ifan indicator indicating that an MTCD is not a low priority MTCD is notincluded, the HeNB judges that the MTCD is a low priority MTCD.

(f) An indicator indicating that an MTCD is a high priority MTCD. If anindicator indicating that a high priority MTCD is not included, the HeNBjudges that the MTCD is a low priority MTCD.

(g) An indicator indicating that an MTCD is not a high priority MTCD. Ifan indicator indicating that an MTCD is not a high priority MTCD is notincluded, the HeNB judges that the MTCD is a high priority MTCD.

While the priority is described to be “low” or “high” here, the priorityindicator does not need to be binary. There may be provided a pluralityof priorities. The priority indicators may be represented as, forexample, integers. As a specific example, the priority indicators arerepresented as “0”, “1”, “2”, and “3”, where the priority becomes higheras the number becomes larger. In the case of this specific example, anMTCD having a priority indicator of “0” or “1” is tolerant of controldelays due to the concentration process, and the HeNB concentrates thedata from this MTCD to a core network. Meanwhile, an MTCD having apriority indicator of “2” or “3” is sensitive to control delays due tothe concentration process, and the HeNB does not concentrate the datafrom this MTCD to a core network.

The following two (1) and (2) are disclosed as specific examples of themethod of notifying a HeNB of the distinction whether or not an MTCD isa low priority MTCD.

(1) The HeNB is notified of the distinction whether an MTCD is a lowpriority MTCD or a high priority MTCD, with the use of the RRC messageor RRC signaling. Alternatively, the priority indicator is mapped to theRRC message or RRC signaling. Specific examples of the RRC signalinginclude “RRC Connection Request” (see Non-Patent Document 2). Contraryto the specific example (2) described below, in the specific example(1), a HeNB can distinguish whether or not a UE is an MTCD beforereceiving the data to the core network, which is a target of theconcentration process. Accordingly, a control delay in the concentrationprocess by a HeNB can be prevented.

(2) The HeNB is notified of the distinction whether an MTCD is a lowpriority MTCD or a high priority MTCD, with the use of the data to thecore network, on which the concentration process is performed. Further,a priority indicator is mapped to the data to the core network(hereinafter, referred to as “core network data” in some cases).Further, a priority indicator may be mapped to a header or footer of thecore network data. If it is possible to distinguish whether a UE is anMTCD or not an MTCD with the use of the header or footer of the corenetwork data, the HeNB is not required to always interpret the contentsof the message from the MTCD to the core network. This reduces theprocessing load of the HeNB.

Next, a specific operation example using the first modification of thefirst embodiment is described with reference to FIG. 18. FIG. 18 is aflowchart showing the procedure by a HeNB regarding the concentrationprocess in the first modification of the first embodiment. The steps ofFIG. 18 corresponding to the steps shown in FIG. 16 are denoted by thesame reference symbols, and the common description is not given here.

This operation example discloses the case of NAS signaling as a specificexample of the data from an MTCD to a core network, which is a target ofthe concentration process by the HeNB. The case in which an MTCDindicator is mapped to the RRC message “RRC Connection Request” isdisclosed as a specific example of the method in which a HeNBdistinguishes whether a user equipment (UE) being served thereby is anMTCD or not an MTCD. The case in which a priority indicator is mapped tothe RRC message “RRC Connection Request” is disclosed as a specificexample of the method in which a HeNB distinguishes whether an MTCDbeing served thereby is a low priority MTCD or a high priority MTCD.

The HeNB sequentially performs the processes of Step ST1601 to StepST1603 described above. In the present modification, the HeNB moves toStep ST1801 in a case of judging that a UE is an MTCD in Step ST1603 ormoves to Step ST1605 in a case of judging that a UE is not an MTCD.

In Step ST1801, the HeNB checks a priority indicator mapped to the RRCmessage and then moves to Step ST1802.

In Step ST1802, the HeNB judges whether or not to have received the RRCmessage from a low priority MTCD, that is, whether or not the MTCD thathas transmitted the RRC message received in Step ST1601 is a lowpriority MTCD, based on the priority indicator checked in Step ST1801.In a case of judging to have received the RRC message from a lowpriority MTCD, that is, judging that the MTCD is a low priority MTCD,the HeNB moves to Step ST1604 and then performs the process describedabove. In a case of judging to not have received the RRC message from alow priority MTCD, that is, judging that the MTCD is not a low priorityMTCD, the HeNB moves to Step ST1605 and performs the process describedabove.

A specific example of the sequence of the mobile communication system inthe first modification of the first embodiment is similar to thesequence of the mobile communication system in the first embodimentshown in FIG. 17 except for that Step ST1801 and Step ST1802 shown inFIG. 18 are provided between Step ST1705 and Step ST1706 shown in FIG.17, which is not shown and described here.

The first modification of the first embodiment can achieve the followingeffects in addition to the effects of the first embodiment. As to anMTCD tolerant of delays, the congestion in a core network can bemitigated as in the first embodiment by executing a process similar tothat of the first embodiment. Moreover, as to an MTCD sensitive to andelay occurrence, the concentration process by the HeNB can be avoided,which enables to avoid an effect due to a control delay through theconcentration process.

Second Modification of First Embodiment

A second modification of the first embodiment discloses a start time andan end time of the first embodiment described above.

A solution in the second modification of the first embodiment isdescribed below. A portion different from the solution in the firstembodiment is mainly described. The portion that is not described hereis as in the first embodiment.

The execution of the process in the first embodiment is started uponinstruction from an MME, SGSN, or the like being a core network. Theexecution of the process in the first embodiment is stopped uponinstruction from the MME, SGSN, or the like being a core network.

The following three (1) to (3) are disclosed as specific examples of atrigger for the MME, SGSN, or the like being a core network to instructa HeNB to start the process (hereinafter, also referred to as“concentration ON”) in the first embodiment (hereinafter, also referredto as “concentration process”). (1) Case where an entity such as an MMEor SGSN being a core network, that is, component is overloaded. (2) Casewhere the processing load of the MME, SGSN, or the like being a corenetwork becomes equal to or larger than a threshold. This may be a casewhere the MTCD-related processing load of the MME, SGSN, or the likebeing a core network becomes equal to or larger than a threshold. (3)Case where the traffic becomes equal to or larger than a threshold. Thismay be a case where the MTCD-related traffic becomes equal to or largerthan a threshold. This traffic may be the traffic between the MME andHeNB or may be the traffic between the SGSN and HeNB.

The following three (1) to (3) are disclosed as specific examples of atrigger for a core network to instruct to stop the concentration process(hereinafter, also referred to as “concentration OFF”). (1) Case wherean entity such as an MME or SGSN being a core network is no longeroverloaded. (2) Case where the processing load of an MME, SGSN, or thelike being a core network falls below a threshold. This may be a casewhere the MTCD-related processing load of the MME, SGSN, or the likebeing a core network falls below a threshold. (3) Case where the trafficfalls below a threshold. This may be a case where the MTCD-relatedtraffic falls below a threshold. This traffic may be the traffic betweenthe MME and HeNB or may be the traffic between the SGSN and HeNB.

Specific examples of the protocol that is used when an MME, SGSN, or thelike being a core network instructs a HeNB about concentration ON orconcentration OFF include S1-AP.

The following four (1) to (4) are disclosed as specific examples of thesignaling for an MME, SGSN, or the like being a core network to instructa HeNB about concentration ON. (1) Signaling that indicatesconcentration ON, initiation, or start is newly provided. (2) Signalingthat indicates termination ON, initiation, or start of an NAS message isnewly provided. (3) Signaling that indicates interpretation ON,initiation, or start of an NAS message is newly provided. (4) “OverloadStart” being the existing S1-AP signaling is used (see TS36.413 V9.3.0(hereinafter, referred to as “Non-Patent Document 14”) by 3GPP).

In the current specifications, an eNB that has received “Overload Start”from an MME performs the process of, for example, rejecting RRCconnection from a user equipment being served thereby. Meanwhile, in thesecond modification of the first embodiment, an eNB that has received“Overload Start” from an MME performs the concentration process on anMTCD being served thereby.

The specific example (4) is more advantageous than the specific examples(1) to (3) in that new signaling is not required to be provided, whichprevents a mobile communication system from becoming complicated. In thecurrent “Overload Start” specifications, access per se from a userequipment being served by an eNB is rejected. Meanwhile, in the specificexample (4), the number of communication times is reduced or the trafficis reduced by performing the concentration process on the data from anMTCD being a UE other than a normal UE, to thereby mitigate anoverloaded state of the core network. The data from a normal UE may betransmitted to a core network as usual. This enables to prevent arejection of access per se from a user equipment being served by an eNB.Therefore, a user-friendly mobile communication system can beconstructed.

The following four (1) to (4) are disclosed as specific examples ofsignaling for an MME, SGSN, or the like being a core network to instructa HeNB about concentration OFF. (1) Signaling that indicatesconcentration OFF, suspension, or stop is newly provided. (2) Signalingthat indicates termination OFF, suspension, or stop of an NAS message isnewly provided. (3) Signaling that indicates interpretation OFF,suspension, or stop of an NAS message is newly provided. (4) “Overloadstop” being the existing S1-AP signaling is used (see Non-PatentDocument 14).

In the current specifications, an eNB that has received “Overload stop”from an MME starts a normal operation on the MME. Meanwhile, in thesecond modification of the first embodiment, an eNB that has received“Overload stop” from an MME stops the concentration process on an MTCDbeing served thereby.

The specific example (4) is more advantageous than the specific examples(1) to (3) in that new signaling is not required to be provided, whichprevents a mobile communication system from becoming complicated. Inaddition, in a case where the overloaded state of the MME is solved, theconcentration process that may cause a delay can be stopped for the datafrom an MTCD being a UE other than a normal UE. Therefore, auser-friendly mobile communication system can be constructed.

Next, a specific operation example using the second modification of thefirst embodiment is described with reference to FIG. 19. FIG. 19 is adiagram showing a sequence of a mobile communication system in thesecond modification of the first embodiment. The MTCD_1 to MTCD_n to beserved by a HeNB are located.

This operation example discloses a case in which the traffic becomesequal to or larger than a threshold as a specific example in which anMME, SGSN, or the like being a core network instructs a HeNB to startthe concentration process. In addition, this operation example disclosesa case in which the traffic falls below a threshold as a specificexample of a trigger for an MME, SGSN, or the like being a core networkto instruct a HeNB to stop the concentration process. This operationexample discloses a case in which signaling that indicates concentrationON is newly provided as a specific example of the signaling for an MME,SGSN, or the like being a core network to instruct a HeNB aboutconcentration ON. In addition, this operation example discloses a casein which signaling that indicates concentration OFF is newly provided asa specific example of the signaling for an MME, SGSN, or the like beinga core network to instruct a HeNB about concentration OFF.

In Step ST1901, the MME judges whether or not the traffic between theMME and HeNB becomes equal to or larger than a threshold. In a case ofjudging that the traffic becomes equal to or larger than the threshold,the MME moves to Step ST1902. In a case of judging that the traffic doesnot become equal to or larger than the threshold, that is, falls belowthe threshold, the MME moves to Step ST1904.

In Step ST1902, the MME notifies the HeNB of signaling that indicatesconcentration ON.

In Step ST1904, the MME notifies the HeNB of signaling that indicatesconcentration OFF.

In Step ST1906, the HeNB judges whether or not to have received thesignaling that indicates concentration ON. In a case of judging to havereceived the signaling that indicates concentration ON, the HeNB movesto Step ST1903. In a case of judging to not have received the signalingthat indicates concentration ON, the HeNB moves to Step ST1905. Thoughnot shown, the HeNB may judge whether or not to have received thesignaling that indicates concentration OFF after judging to not havereceived the signaling that indicates concentration ON in Step ST1906.In a case of judging to have received the signaling that indicatesconcentration OFF, the HeNB may move to Step ST1905. In a case ofjudging to not have received the signaling that indicates concentrationOFF, the HeNB may perform a normal process.

In Step ST1903, the HeNB executes the concentration process on the datafrom an MTCD being served thereby to a core network. In Step ST1903, theHeNB may omit a normal process in a case of receiving “RRC ConnectionRequest” (see Non-Patent Document 2). In Step ST1903, the HeNB maynotify the MTCD that has transmitted “RRC Connection Request” of “RRCConnection reject”. The information indicating that the data from theMTCD to the core network has been received may be mapped to “RRCConnection reject”. The information for requesting the retransmission ofdata from the MTCD to the core network may be mapped to “RRC Connectionreject”.

In Step ST1905, the HeNB does not execute the concentration process onthe data from the MTCD being served thereby to the core network.

While the present modification has mainly described an example incombination with the first embodiment, the present modification can beused also in combination with the first modification of the firstembodiment.

The second modification of the first embodiment can achieve thefollowing effects in addition to the effects of the first embodiment.With the use of the second modification of the first embodiment, in acase where the core network becomes congested or the entity of the corenetwork becomes overloaded, the concentration process by the HeNB can bestarted by the decision of the core network. Upon initiation of theconcentration process, it is possible to mitigate the congestion in thecore network while keeping the service for a user equipment.

Further, in a case where the congestion of the core network is mitigatedor the overloaded state of the entity of the core network is solved, theconcentration process by the HeNB can be stopped by the decision of thecore network. Contrary to the first embodiment regarding the method ofconcentrating the data from MTCDs being served by a HeNB to a corenetwork, a control delay of MTCD service, which occurs in theconcentration process, is solved because the concentration process isstopped, and a user-friendly mobile communication system can beconstructed.

Third Modification of First Embodiment

In a case where the second modification of the first embodimentdescribed above is used, the following problem arises. Considered hereis a case in which a HeNB with the capability of performing aconcentration process and a HeNB without the capability of performing aconcentration process are located. It is useless to execute the processof the second modification of the first embodiment on a HeNB without thecapability of performing a concentration process by an MME, SGSN, or thelike being a core network to notify the instruction to start or stop theconcentration process. Specifically, unused communication resources fromthe core network to the HeNB and unnecessary process by the core networkare generated.

A solution in a third modification of the first embodiment is describedbelow. A portion different from the solutions in the first embodimentand the second modification of the first embodiment is mainly described.The portion that is not described here is as in the first embodiment andthe second modification of the first embodiment.

The HeNB informs an MME, SGSN, or the like being a core network of thecapability information regarding the concentration process for the datafrom the MTCD. The core network executes the process of the secondmodification of the first embodiment described above on a HeNB with thecapability of performing a concentration process for the data from theMTCD.

The following three (1) to (3) are disclosed as specific examples of thecapability information regarding the concentration process notified thecore network by the HeNB; (1) information indicating whether or not thedata from an MTCD can be concentrated, information indicating that thedata from an MTCD can be concentrated, or information indicating thatthe data from an MTCD cannot be concentrated, (2) information indicatingwhether or not NAS signaling can be interpreted, information indicatingthat NAS signaling can be interpreted, or information indicating thatNAS signaling cannot be interpreted, and (3) information indicatingwhether or not NAS signaling can be terminated, information indicatingthat NAS signaling can be terminated, or information indicating that NASsignaling cannot be terminated.

Among the specific examples of the capability information regarding theconcentration process, the use of the (1) information indicating thatthe data from an MTCD can be concentrated, (2) information indicatingthat NAS signaling can be interpreted, and (3) information indicatingthat NAS signaling can be terminated is effective in that a HeNB withoutthe capability of performing a concentration process does not need tonotify the core network of the capability information regarding theconcentration process.

The following three (1) to (3) are disclosed as specific examples of thetiming at which a HeNB notifies a core network of the capabilityinformation regarding a concentration process. (1) Time when a HeNB isinstalled. In a case where the capability of a HeNB to perform aconcentration process remains unchanged, such an effect that thegeneration of unused communication resources is prevented can beachieved. (2) Periodically. This is effective in a case where thecapability of a HeNB to perform a concentration process is changed. Inaddition, the capability information is notified periodically, leadingto an effect of high resistance to communication error. (3) Time whenthe capability of a HeNB changes. This is effective in a case in whichthe capability of a HeNB to perform a concentration process changes.Contrary to the specific example (2), notification is made only when thecapability changes, whereby an effect that the generation of unusedcommunication resources is prevented can be achieved.

The following three (1) to (3) are disclosed as specific examples ofsignaling when a HeNB notifies a core network of the capabilityinformation regarding a concentration process.

(1) S1 signaling or S1 message is newly provided. S1 signaling forcontrol may be provided. Alternatively, S1 signaling that does notrequire a response message from an MME, SGSN, or the like being areceiver may be provided. S1 signaling that does not require a responsemessage is also referred to as “Class 2” (see Non-Patent Document 14).S1 signaling that is not associated with a user equipment may beprovided. S1 signaling that is not associated with a user equipment isalso referred to as “non UE associated signaling” (see Non-PatentDocument 14). Examples of the parameter mapped to the newly provided S1signaling include the “capability information regarding theconcentration process of notifying a core network by a HeNB” describedabove.

(2) S1 signaling or S1 message is newly provided. S1 signaling forcontrol may be provided. Alternatively, S1 signaling that requires aresponse message from an MME, SGSN, or the like being a receiver may beprovided. S1 signaling that requires a response message is also referredto as “class 1” (see Non-Patent Document 14). Alternatively, S1signaling that is not associated with a user equipment may be provided.Examples of the parameter mapped to a newly provided S1 signalinginclude “capability information regarding the concentration processnotified a core network by a HeNB” described above.

(3) The existing S1 signaling is used. The existing S1 signaling forcontrol may be used. Alternatively, the existing S1 signaling that isnot associated with a user equipment may be used. Examples of theparameter that needs to be added to the existing S1 signaling include“capability information regarding the concentration process notified acore network by a HeNB” described above. This is more advantageous thanthe specific examples (1) and (2) in that new signaling is not requiredto be provided, which prevents a mobile communication system frombecoming complicated.

Next, the following two (a) and (b) are disclosed as specific examplesof the existing S1 signaling.

(a) “S1 SETUP REQUEST” (see Non-Patent Document 14). The purpose of “S1SETUP REQUEST” is to exchange application level data needed for the eNBand MME to interoperate correctly on the S1 interface. The containedparameter is the information specific to an eNB, such as a CSG-ID,global cell identity, and TAC of an eNB. Similarly, the capabilityinformation regarding the concentration process of the HeNB is theinformation specific to a HeNB. Therefore, with the use of “S1 SETUPREQUEST” for notifying a core network of the capability informationregarding the concentration process by a HeNB, an MME that receives “S1SETUP REQUEST” can obtain the information specific to a HeNB at once.This leads to effects that the processing load of an MME is reduced anda control delay as a mobile communication system is prevented.

(b) “eNB Configuration Update” (see Non-Patent Document 14). The purposeof “eNB Configuration Update” is to update application level data neededfor the eNB and MME to interoperate correctly on the S1 interface. Thealready contained parameter is the information specific to an eNB suchas a CSG-ID and TAC of an eNB. Similarly, the capability informationregarding the concentration process by a HeNB is the informationspecific to a HeNB. Therefore, with the use of “eNB ConfigurationUpdate” for notifying a core network of the capability informationregarding the concentration process by a HeNB, an MME that receives “eNBConfiguration Update” can obtain the information specific to a HeNB atonce. This leads to effects that the processing load of an MME isreduced and a control delay as a mobile communication system isprevented.

Next, a specific operation example using the third modification of thefirst embodiment is described with reference to FIG. 20. FIG. 20 is adiagram showing a sequence of a mobile communication system in the thirdmodification of the first embodiment. The steps of FIG. 20 correspondingto the steps shown in FIG. 19 are denoted by the same reference symbols,and the common description is not given here.

This operation example discloses a time when a HeNB is installed as aspecific example of the timing at which a HeNB notifies a core networkof the capability information regarding a concentration process.

In Step ST2001, a HeNB is installed. In Step ST2002, the HeNB notifiesan MME of the capability information regarding the concentration processby the HeNB. The MME that has received the capability informationregarding the concentration process stores and manages this information.

In Step ST2003, the MME judges whether or not the HeNB has thecapability of performing a concentration process based on the capabilityinformation regarding the concentration process which has been receivedin Step ST2002. In a case of judging that the HeNB has the capability ofperforming a concentration process, the MME moves to Step ST1901. In acase of judging that the HeNB does not have the capability of performinga concentration process, the MME ends the process, which is notessential in the present embodiment and thus is not described here.

After it is judged that the HeNB has the capability of performing aconcentration process in Step ST2003, the MME and HeNB perform theprocesses of Step ST1901 to Step ST1906 as in FIG. 19 described above.As shown in FIG. 20, the process of Step ST1901 is performed after theprocess of Step ST2003 in the present modification. Alternatively, theprocess of Step ST2003 and the process of Step ST1901 may be performedin an arbitrary order, or the process of Step ST2003 may be performedafter the process of Step ST1901.

While the present modification has mainly described an example incombination with the first embodiment and the second modification of thefirst embodiment, the present modification can be used also incombination with the first modification of the first embodiment.

The third modification of the first embodiment can achieve the followingeffects in addition to the effects of the first embodiment and thesecond modification of the first embodiment. It is possible to prevent acore network from notifying a HeNB without the capability of performinga concentration process of the instruction to start and stop theconcentration process. Accordingly, communication resources from a corenetwork to a HeNB can be used effectively and the processing load of thecore network can be reduced.

Fourth Modification of First Embodiment

The fourth modification of the first embodiment discloses anothersolution to the same problem as that of the third modification of thefirst embodiment. The solution in the fourth modification of the firstembodiment is described below. A portion different from the solutions inthe first embodiment and the second modification of the first embodimentis mainly described. A portion that is not described here is as in thefirst embodiment and the second modification of the first embodiment.

In the fourth modification of the first embodiment, the MME, SGSN, orthe like being a core network executes the process of the secondmodification of the first embodiment on a HeNB with the capability ofperforming a concentration process as well as a HeNB without thecapability of performing a concentration process. The operation isvaried depending on whether or not a HeNB has the capability ofperforming a concentration process among the HeNBs that have receivedthe instruction to start or stop the concentration process.

The first embodiment, the first modification of the first embodiment,and the second modification of the first embodiment are specificexamples of the operation of a HeNB with the capability of performing aconcentration process.

Specific examples of the operation of a HeNB without the capability ofperforming a concentration process are disclosed below. First, thefollowing four (1) to (4) are disclosed as specific examples of theoperation of the HeNB that has received an instruction to start theconcentration process from the MME, SGSN, or the like being a corenetwork.

(1) The HeNB stops or rejects the transmission/reception of the datato/from the MME, SGSN, or the like being a core network by a userequipment being served thereby. Specific examples of the data to the MMEinclude NAS message and NAS signaling.

(2) The HeNB rejects signaling related to RRC connection from a userequipment being served thereby. Specific examples of the signalingrelated to RRC connection include “RRC CONNECTION REQUEST” and “RRCCONNECTION Reestablishment Request” (see Non-Patent Document 2).

(3) The HeNB performs the operation when receiving “Overload Start” fromthe current MME (see Non-Patent Document 14). Specifically, the HeNBrejects the establishment of RRC connection other than one for anemergency call.

(4) Combination of (1) to (3) above.

The execution of a normal operation is a specific example of theoperation by a HeNB that has received the instruction to stop aconcentration process from an MME, SGSN, or the like being a corenetwork.

Next, a specific operation example using the fourth modification of thefirst embodiment is described with reference to FIG. 21. FIG. 21 is adiagram showing a sequence of a mobile communication system in thefourth modification of the first embodiment. The steps of FIG. 21corresponding to the steps shown in FIG. 19 are denoted by the samereference symbols, and the common description is not given here.

This operation example discloses a case in which “Overload Start” beingthe current S1-AP signaling is used as a specific example of thesignaling for a core network to instruct a HeNB about concentration ON.In addition, this operation example discloses a case in which “Overloadstop” being the current S1-AP signaling is used as a specific example ofthe signaling for a core network to instruct a HeNB about concentrationOFF. Further, this operation example discloses a case in which theoperation when the current “Overload Start” is received is performed asan operation example in a case where a HeNB without the capability ofperforming a concentration process receives an instruction to start theconcentration process from a core network.

In Step ST1901, the MME judges whether or not the traffic between theMME and HeNB becomes equal to or larger than a threshold. In a case ofjudging that the traffic becomes equal to or larger than the threshold,the MME moves to Step ST2101. In a case of judging that the traffic doesnot become equal to or larger than the threshold, that is, falls belowthe threshold, the MME moves to Step ST2104.

In Step ST2101, the MME notifies the HeNB of “Overload Start”. In StepST2104, the MME notifies the HeNB of “Overload Stop”.

In Step ST2107, the HeNB judges whether or not to have received“Overload Start”. In a case of judging to have received “OverloadStart”, the HeNB moves to Step ST2102. In a case of judging to not havereceived “Overload Start”, the HeNB moves to Step ST2105. Though notshown, the HeNB may judge whether or not to have received “OverloadStop” after judging to not have received “Overload Start” in StepST2107. Then, the HeNB may move to Step ST2105 in a case of judging tohave received “Overload Stop” or move to Step ST2106 in a case ofjudging to not have received “Overload Stop”.

In Step ST2102, the HeNB judges whether or not the own cell has thecapability of performing a concentration process. In a case of judgingto have the capability of performing a concentration process, the HeNBmoves to Step ST1903. In a case of judging to not have the capability ofperforming a concentration process, the HeNB moves to Step ST2103.

In Step ST1903, the HeNB executes the concentration process on the datafrom an MTCD being served thereby to a core network, and ends theprocess. In Step ST2103, the HeNB rejects the establishment of RRCconnection other than one for an emergency call from a user equipmentbeing served thereby and ends the process.

In Step ST2105, the HeNB judges whether or not the own cell has thecapability of performing a concentration process. In a case of judgingto have the capability of performing a concentration process, the HeNBmoves to Step ST1905. In a case of judging to not have the capability ofperforming a concentration process, the HeNB moves to Step ST2106.

In Step ST1905, the HeNB does not execute the concentration process onthe data from an MTCD being served thereby to the core network. In StepST2106, the HeNB operates normally.

The judgment process of Step ST2105 may be omitted such that the HeNBthat has received “Overload Stop” from the MME in Step ST2104 moves toStep ST2106 and performs a normal operation irrespective of the presenceor absence of the capability of performing a concentration process.

While the present modification has mainly described the example incombination with the first embodiment and the second modification of thefirst embodiment, the present modification can be used also incombination with the first modification of the first embodiment.

The fourth modification of the first embodiment can achieve thefollowing effects in addition to the effects in the first embodiment andthe second modification of the first embodiment. Contrary to the thirdmodification of the first embodiment, the HeNB does not need to notifythe core network of the capability information of the own cell regardingthe concentration process, and the communication resources between theHeNB and core network can be used effectively.

Further, the core network does not need to store the presence or absenceof the capability of a HeNB being served thereby to perform aconcentration process and vary the operation depending on the presenceor absence of the capability regarding the concentration process (seeStep ST2003 in FIG. 20), which reduces the processing load of the corenetwork.

In a case where the core network becomes congested and the core networknotifies the HeNB of the signaling for instructing concentration ON, thecommunication between the HeNB and core network or the operation leadingto a reduction of the processing load of the core network is startedirrespective of whether or not the HeNB has the capability of performinga concentration process (see Step ST2103 and Step ST1903 in FIG. 21).Therefore, it is possible to avoid the congestion in the core networkirrespective of whether or not the HeNB has the capability of performinga concentration process.

Second Embodiment

A second embodiment discloses a specific method of transmitting datafrom a HeNB to an MME, SGSN, or the like being a core network after theHeNB performs a concentration process using the first embodiment.

A solution in the second embodiment is described below. A HeNB serves asa trigger or origin, and transmits data from an MTCD being servedthereby to an MME, SGSN, MTC server, or the like being a core network.

The following two (1) and (2) are disclosed as specific examples of thecondition that a HeNB serves as a trigger of the data transmission to anMME, SGSN, MTC server, or the like being a core network from an MTCDbeing served thereby.

(1) A HeNB transmits the data from an MTCD being served thereby to acore network irrespective of the reception of the uplink data from theMTCD being served thereby. This transmission may be performed over theresources for MTCD. Specific examples of the resources for MTCD includea time at which the communication for MTCD is allowed, a period in whichthe communication for MTCD is allowed, and a resource in which thecommunication for MTCD is allowed. The time or period when thecommunication for MTCD is allowed is equivalent to an allowed period.The resource in which the communication for MTCD is allowed isequivalent to an allowed resource. The resources for MTCD may beconfigured or updated by the MME, SGSN, MTC server, or the like being acore network for the HeNB or may be determined in a static manner, thatis, determined in advance.

According to Non-Patent Document 9 described above, a message is heldfor a determined time period from the point in time when the eNBreceives the message from the MTCD. Meanwhile, in this specific example,a message is transmitted to the core network at the time when, forexample, the communication for MTCD is allowed irrespective of the pointin time when a HeNB receives the message from an MTCD. Therefore, inthis specific example, the core network is capable of grasping the timeat which the transmission for MTCD may be performed from a HeNB.According to Non-Patent Document 9, the core network cannot grasp thepoint in time when an eNB receives a message from an MTCD, and thuscannot grasp the time at which an eNB may perform the transmission forMTCD based on the point in time of receiving the message from an MTCD.Therefore, in this specific example, the core network can adjust theload due to an MTCD more easily compared with Non-Patent Document 9.

TR 23.888 V0.5.1 (hereinafter, referred to as “Non-Patent Document 15”)by 3GPP discloses that a network operator allows MTCDs to access anetwork during only a pre-defined period. Meanwhile, in this specificexample, it is not required to set a period during which MTCDs areallowed to access a network. Accordingly, it is not required to notify alarge number of MTCDs of the allowed period or set the allowed period bya core network, whereby radio resources can be used effectively.Moreover, it is not required to manage the time of each MTCD in a corenetwork or achieve synchronization between the core network and MTCD inthis specific example, which prevents a communication system frombecoming complicated.

(2) A HeNB transmits the data from an MTCD being served thereby to anMME, SGSN, MTC server, or the like being a core network upon receptionof the uplink data from the MTCD being served thereby.

The following two (a) and (b) are disclosed as specific examples of theuplink data from an MTCD.

(a) Reception of RRC message or RRC signaling. Non-Patent Document 9discloses that an eNB transmits data from an MTCD to a core network uponreception of NAS signaling. In this specific example, the data from anMTCD to a core network is transmitted upon reception of RRC signaling.This enables to prepare the concentration process at an earlier stagecompared with Non-Patent Document 9. The HeNB may transmit the data froman MTCD being served thereby to a core network after a lapse of apre-determined time period or after a lapse of a time period set by acore network from the point in time when receiving the RRC message.Alternatively, in a case of receiving RRC messages from MTCDs beingserved thereby a pre-determined number of times, the HeNB may transmitthe data from the MTCDs being served thereby to a core network.

(b) Reception of the uplink data transmitted in a communication systemother than the mobile communication system standardized by 3GPP.According to this specific example, even in a case where an MTCD isinstalled in a poor radio environment for a mobile communication systemstandardized by 3GPP, the HeNB is capable of transmitting the data fromthe MTCD being served thereby to a core network upon reception of theuplink data from the MTCD being served thereby, as described in thespecific example (2) above.

The HeNB may transmit the data from an MTCD being served thereby to acore network after a lapse of a pre-determined time period or after alapse of a time period set by the core network from the point in time ofreceiving the uplink data transmitted in a communication system otherthan the mobile communication system standardized by 3GPP.Alternatively, in a case of receiving the uplink data transmitted fromMTCDs being served thereby a pre-determined number of times in acommunication system other than the mobile communication systemstandardized by 3GPP, the HeNB may transmit the data from MTCDs beingserved thereby to a core network.

Disclosed below is a specific example of signaling when a HeNB transmitsthe data from an MTCD being served thereby to an MME, SGSN, MTC server,or the like being a core network via the S-GW. The data is transmittedby means of a user datagram protocol (UDP) (see Non-Patent Document 13).The data may be user data.

Disclosed below is a specific example of signaling when a HeNB transmitsthe data from an MTCD being served thereby to an MME, SGSN, MTC server,or the like being a core network via the MME. The S1 interface (alsoreferred to as “S1-MME” or “S1-U”) is used. The data may be controldata.

Another specific example when a HeNB transmits data from an MTCD beingserved thereby to a core network by means of an S1 interface isdisclosed below. S1 signaling or S1 message is newly provided. S1signaling for control may be provided. Alternatively, S1 signaling thatdoes not require a response message from an MME, SGSN, or the like beinga receiver may be provided. The S1 signaling that does not require aresponse message is also referred to as “Class 2” (see Non-PatentDocument 14). Still alternatively, S1 signaling that is not associatedwith a user equipment may be provided. The S1 signaling that is notassociated with a user equipment is also referred to as “non UEassociated Signaling” (see Non-Patent Document 14).

The following eight (1) to (8) are disclosed as specific examples ofparameters to be mapped to S1 signaling to be newly provided. (1) HeNBidentity. The receiver is capable of identifying via which HeNB the datahas been transmitted, and thus, the identity may be physical cellidentity (PCI), cell global identity (CGI), or the like. (2) MTCDidentity. The receiver is capable of identifying from which MTCD thedata has been transmitted, and thus, the identity may be an IMSI or aproduction number of an MTCD. This parameter may be provided for thenumber of MTCDs on which the concentration process is performed, thatis, for the same number as the number of MTCDs on which theconcentration process is performed. (3) Protocol data unit (PDU) forMTC. The PDU is an aggregation of pieces of data meaningful between peerlayers. This enables to map data from an MTCD to a core network on S1signaling to be newly provided. This parameter may be provided for thenumber of MTCDs on which the concentration process is performed, thatis, for the same number as the number of MTCDs on which theconcentration process is performed. (4) Service data unit (SDU) for MTC.The SDU is an aggregation of pieces of data requested to be transferredfrom upper layers. This enables to map, to the core network on S1signaling to be newly provided, the data from the MTCD. This parametermay be provided for the number of MTCDs on which the concentrationprocess is performed, that is, for the same number as the number ofMTCDs on which the concentration process is performed. (5) Service typeor service identity. This enables to support a case in which thetransmission destination of data differs among services. Further, evenif one MTCD supports a plurality of services, it is possible to support,for example, a case in which the transmission destination of datadiffers among services. (6) Information indicating to which MTC serverthe data is directed or to which MTC the user data is directed. Specificexamples thereof include an MTC server identity and an MTC useridentity. This enables to appropriately change the transmissiondestination. (7) Identity or index indicating the combination of (5) and(6) above. (8) Combination of (1) to (7) above.

Next, a specific operation example using the second embodiment isdescribed with reference to FIG. 22. FIG. 22 is a diagram showing asequence of a mobile communication system in the second embodiment. Thesteps of FIG. 22 corresponding to the steps shown in FIG. 17 and FIG. 19are denoted by the same reference symbols, and the common description isnot given here.

This operation example discloses, as a specific example of the conditionin which a HeNB serves as a trigger of the data transmission from anMTCD being served thereby to a core network, a case in which the HeNBtransmits the data from an MTCD being served thereby to a core networkirrespective of the reception of the uplink data from the MTCD beingserved thereby. In addition, this operation example discloses a case inwhich the transmission to the core network is performed during a periodin which the communication for MTCD is allowed.

In Step ST2201, the MME notifies the HeNB of the period informationindicating the period in which the HeNB is allowed to transmit the datafrom MTCDs being served thereby to a core network. In other words, theMME notifies the HeNB of the period information indicating a period inwhich the communication for MTCD is allowed.

Then, the MTCD_1 performs the process of Step ST1703 described above,and the MTCD_n performs the process of Step ST1704 described above. TheHeNB that has received “RRC Connection Requests” transmitted from theMTCD_1 and MTCD_n performs the processes of Step ST1705 and Step ST1903described above. After ending the process of Step ST1903, the HeNB movesto Step ST2202.

In Step ST2202, the HeNB judges whether or not the period is one inwhich communication for MTCD is allowed, based on the period informationreceived in Step ST2201. In a case of judging that the period is one inwhich the communication for MTCD is allowed, the HeNB moves to StepST2203. In a case of judging that the period is not one in which thecommunication for MTCD is allowed, the HeNB repeats the judgment processof Step ST2202.

In Step ST2203, the HeNB transmits the data from MTCDs being servedthereby to a core network by means of the S1 interface. In actuality,the processes corresponding to those of Step ST1705, Step ST1903, andStep ST2202 are performed after the process of Step ST1703 in thisoperation example, which are not shown and described for easyunderstanding.

In a case of judging that the data is not from the MTCD in Step ST1705,the HeNB ends the process, which is not essential in the presentembodiment and thus is not described here. Alternatively, in a case ofjudging that the data is not from an MTCD in Step ST1705, the HeNB mayperform a process similar to that of Step ST2202 and show that there isno data from an MTCD during a period in which the communication for MTCDis allowed. For example, “empty” may be notified. This causes the MME toreceive any data during a period in which the communication for MTCD isallowed, leading to a reduction of communication errors between the HeNBand MME.

It is conceivable that the HeNB may receive an RRC message from an MTCDbeing served thereby and perform the processes corresponding to those ofStep ST1705, Step ST1903, and Step ST2202 while repeating the judgmentprocess of Step ST2202, which is not described here for easyunderstanding.

Next, a specific operation example using the second embodiment isdescribed with reference to FIG. 23. FIG. 23 is a diagram showing asequence of the mobile communication system in the second embodiment.The steps of FIG. 23 corresponding to the steps shown in FIG. 17 andFIG. 22 are denoted by the same reference symbols, and the commondescription is not given here.

This operation example discloses, as a specific example of the conditionin which a HeNB serves as a trigger of the transmission of data from anMTCD being served thereby to a core network, a case in which the HeNBtransmits the data from the MTCD being served thereby to the corenetwork upon reception of the uplink data from the MTCD being servedthereby. In addition, this operation example discloses a case of RRCsignaling as a specific example of uplink data.

In Step ST2301, the MME sets, for the HeNB, the time period from thereception of the RRC message to the transmission of the data from theMTCD to the core network. In other words, the MME sets, for the HeNB,the concentration process time period being a time period from thereception of the RRC message to the concentration process.

Then, in Step ST1703, the MTCD_1 performs the process of transmitting“RRC Connection Request” to the HeNB and, in Step ST1704, the MTCD_nperforms the process of transmitting “RRC Connection Request” to theHeNB. The HeNB that has received “RRC Connection Requests” transmittedfrom the MTCD_1 and MTCD_n performs the processes of Step ST1705 andStep ST1903 described above. The HeNB moves to Step ST2302 after endingthe process of Step ST1903.

In Step ST2302, the HeNB judges whether or not the concentration processtime period set in Step ST2301 has elapsed from the reception of the RRCmessage. In the case of judging that the concentration process timeperiod has elapsed, the HeNB moves to Step ST2203. In the case ofjudging that the concentration process time period has not elapsed, theHeNB repeats the judgment process of Step ST2302. In this operationexample, the HeNB performs the process of judging whether or not theconcentration process time period has elapsed in Step ST2302.Alternatively, the HeNB may perform the process of judging whether ornot the concentration process time period has elapsed from the receptionof the RRC message first received after the last transmission of thedata from the MTCD being served thereby to the core network.

In actuality, the processes corresponding to those of Step ST1705, StepST1903, and Step ST2302 are performed after the process of Step ST1703in this operation example, which are not described here for easyunderstanding.

In a case of judging that the data is not from the MTCD in Step ST1705,the HeNB ends the process, which is not essential in the presentembodiment and thus is not described here. Alternatively, in a case ofjudging that the data is not from the MTCD in Step ST1705, the HeNB mayperform a process similar to that of Step ST2202 to show that there isno data from the MTCD during a period in which the communication forMTCD is allowed. For example, “empty” may be notified. This causes theMME to receive any data during the period in which the communication forMTCD is allowed, leading to a reduction of communication errors betweenthe HeNB and MME.

It is also conceivable that the HeNB may separately receive the RRCmessage from an MTCD being served thereby and perform the processescorresponding to those of Step ST1705, Step ST1903, and Step ST2302while repeating the judgment process of Step ST2302, which is notdescribed here for easy understanding.

While the present embodiment has mainly described the example incombination with the first embodiment, the present embodiment can beused also in combination with the first modification of the firstembodiment, the second modification of the first embodiment, the thirdmodification of the first embodiment, and the fourth modification of thefirst embodiment.

The present embodiment can also be used when an eNB holds back andaggregates the signaling messages common to the MTCD group, which isdisclosed in Non-Patent Document 9.

The second embodiment can achieve the following effects. It is possibleto establish the method in which a HeNB performs the concentrationprocess on the data from an MTCD being served thereby to the corenetwork, and then the HeNB transmits the data to the core network.

First Modification of Second Embodiment

A first modification of the second embodiment discloses another specificexample of the second embodiment when the HeNB transmits the data froman MTCD being served thereby to the MME, SGSN, MTC server, or the likebeing a core network via the MME by means of the S1 interface.

S1 signaling or S1 message is newly provided. S1 signaling for controlmay be provided. Alternatively, S1 signaling that requires a responsemessage from an MME, SGSN, or the like being a receiver may be provided.The S1 signaling that requires a response message is also referred to as“Class1” (see Non-Patent Document 14).

In a case of receiving a message indicating success, for example,“Successful message” or “Ack message” in the response message from theMME, the HeNB may transmit the next data. In a case of receiving amessage indicating failure, for example, “Unsuccessful message”,“failure message”, or “Nack message” in the response message from theMME, the HeNB may perform retransmission. Alternatively, S1 signalingthat is not associated with a user equipment may be provided. The S1signaling that is not associated with a user equipment is also referredto as “non UE associated Signaling” (see Non-Patent Document 14).

Specific examples of parameters mapped to the S1 signaling to be newlyprovided are similar to those of the second embodiment above, which arenot described here.

Next, a specific operation example using the first modification of thesecond embodiment is described with reference to FIG. 24. FIG. 24 is adiagram showing a sequence of a mobile communication system in the firstmodification of the second embodiment. The steps of FIG. 24corresponding to the steps shown in FIG. 17 and FIG. 22 are denoted bythe same reference symbols, and the common description is not givenhere.

This operation example discloses, as a specific example of the conditionin which a HeNB serves as a trigger for the transmission from an MTCDbeing served thereby to a core network, a case in which a HeNB transmitsthe data from the MTCD being served thereby to the core networkirrespective of the reception of uplink data from the MTCD being servedthereby. In addition, this operation example discloses a case in whichthe transmission to the core network is performed during a period inwhich the communication for MTCD is allowed.

The MME performs the process of Step ST2201 described above. Then, inStep ST1703, the MTCD_1 performs the process of transmitting “RRCConnection Request” to the HeNB and, in Step ST1704, the MTCD_n performsthe process of transmitting “RRC Connection Request” to the HeNB. TheHeNB that has received “RRC Connection Requests” transmitted from theMTCD_1 and MTCD_n performs the processes of Step ST1705 and Step ST1903described above. The HeNB performs the processes of Step ST2202 and StepST2203 described above after ending the process of Step ST1903.

Then, in Step ST2401, the MME, which has received the data from the MTCDbeing served thereby to the core network through signaling by means ofthe S1 interface of class 1 from the HeNB in Step ST2203, transmits aresponse message in response to the message of the received data to theHeNB.

Then, in Step ST2402, the HeNB judges whether or not to have received amessage indicating success, for example, Ack message. Specifically, theHeNB judges whether or not the response message received in Step ST2401is a message indicating success, for example, Ack message. In a case ofjudging that the response message is a message indicating success, forexample, Ack message, the HeNB moves to Step ST2404. In a case ofjudging that the response message is not a message indicating success,that is, the response message is a message indicating failure, forexample, Nack message, the HeNB moves to Step ST2403.

In Step ST2403, the HeNB retransmits the data from the MTCD being servedthereby to the core network, which has been transmitted in Step ST2203,and then returns to Step ST2402 to repeat the judgment process.

In Step ST2404, the HeNB transmits, to the MME, the next data from theMTCD being served thereby to the core network by means of the S1interface.

While the present modification has mainly described the example incombination with the first embodiment, the present modification can beused also in combination with the first modification of the firstembodiment, the second modification of the first embodiment, the thirdmodification of the first embodiment, and the fourth modification of thefirst embodiment.

The present modification can also be used when an eNB holds back andaggregates the signaling messages common to the MTCD group, which isdisclosed in Non-Patent Document 9.

The first modification of the second embodiment can achieve thefollowing effects. It is possible to establish the method in which aHeNB performs the concentration process on the data from an MTCD beingserved thereby to a core network, and then, the HeNB transmits the datato the core network.

Second Modification of Second Embodiment

A second modification of the second embodiment discloses anotherspecific example of the second embodiment when the HeNB transmits thedata from an MTCD being served thereby to an MME, SGSN, MTC server, orthe like being a core network via the MME by means of the S1 interface.The existing S1 signaling or S1 message is used. The existing S1signaling for control may be used. Alternatively, the existing S1signaling that is not associated with a user equipment may be used.

The following five (1) to (5) are disclosed as specific examples of theparameters required for the existing S1 signaling when a HeNB transmitsthe data from an MTCD being served thereby to an MME, SGSN, MTC server,or the like being a core network via the MME by means of the S1interface; (1) HeNB identity, (2) MTCD identity, which may be providedfor the number of MTCDs on which the concentration process is performed,that is, for the same number as the number of MTCDs on which theconcentration process is performed, (3) PDU or SDU for MTC, which may beprovided for the number of MTCDs on which the concentration process isperformed, that is, for the same number as the number of MTCDs on whichthe concentration process is performed, (4) service type or serviceidentity, and (5) information indicating to which MTC server the data isdirected or to which MTC user the data is directed.

Next, the following two (a) and (b) are disclosed as specific examplesof the existing S1 signaling.

(a) “S1 SETUP REQUEST” (see Non-Patent Document 14). The parametersmapped to “S1 SETUP REQUEST” contain “Global eNB ID” being a HeNBidentity of the specific example (1) of the parameters required for theexisting S1 signaling. Therefore, parameters required to be newly addedto “S1 SETUP REQUEST” are the MTCD identity of the specific example (2),the PDU or SDU for MTC of the specific example (3), the service type orservice identity of the specific example (4), and the informationindicating to which MTC server the data is directed or to which MTC userthe data is directed of the specific example (5). The MTCD identity maybe provided for the number of MTCDs on which the concentration processis performed, that is, for the same number as the number of MTCDs onwhich the concentration process is performed. The PDU or SDU for MTC maybe provided for the number of MTCDs on which the concentration processis performed, that is, for the same number as the number of MTCDs onwhich the concentration process is performed.

A parameter indicating that the data from an MTCD has been correctlyreceived may be added to “S1 SETUP RESPONSE” being a response messageindicating success, which is transmitted from the MME in response to “S1SETUP REQUEST”. The HeNB that has received “S1 SETUP RESPONSE” includingthe parameter indicating that the data has been correctly received maytransmit the next data from the MTCD. Alternatively, the HeNB that hasreceived “S1 SETUP RESPONSE” may transmit the next data from the MTCD,without newly providing the parameter indicating that the data has beencorrectly received. A parameter indicating that the data from the MTCDhas not been correctly received may be added to “S1 SETUP FAILURE” beinga response message indicating failure, which is transmitted from the MMEin response to “S1 SETUP REQUEST”. The HeNB that has received “S1 SETUPFAILURE” including the parameter indicating that the data has not beencorrectly received may retransmit the same data from the MTCD.Alternatively, the HeNB that has received “S1 SETUP FAILURE” mayretransmit the same data from the MTCD, without newly providing theparameter indicating that the data has not been correctly received.

(b) “eNB Configuration Update” (see Non-Patent Document 14). Theparameters mapped to “eNB Configuration Update” include “eNB Name” beinga HeNB identity of the specific example (1), which is the parameterrequired for the existing S1 signaling described above. Therefore,parameters required to be newly added to “S1 SETUP REQUEST” are the MTCDidentity of the specific example (2), the PDU or SDU for MTC of thespecific example (3), the service type or service identity of thespecific example (4), and the information indicating to which MTC serverthe data is directed or to which MTC user the data is directed of thespecific example (5). The MTCD identity may be provided for the numberof MTCDs on which the concentration process is performed, that is, forthe same number as the number of MTCDs on which the concentrationprocess is performed. The PDU or SDU for MTC may be provided for thenumber of MTCDs on which the concentration process is performed, thatis, for the same number as the number of MTCDs on which theconcentration process is performed.

A parameter indicating that the data from an MTCD has been correctlyreceived may be added to “eNB Configuration Update Acknowledge” being aresponse message indicating success, which is transmitted from the MMEin response to “eNB Configuration Update”. The HeNB that has received“eNB Configuration Update Acknowledge” including the parameterindicating that the data has been correctly received may transmit thenext data from the MTCD. Alternatively, the HeNB that has received “eNBConfiguration Update Acknowledge” may transmit the next data from theMTCD, without newly providing the parameter indicating that the data hasbeen correctly received. A parameter indicating that the data from theMTCD has not been correctly received may be added to “eNB ConfigurationUpdate FAILURE” being a response message indicating failure, which istransmitted from the MME in response to “eNB Configuration Update”. TheHeNB that has received “eNB Configuration Update FAILURE” including theparameter indicating that the data has not been correctly received mayretransmit the same data from the MTCD. Alternatively, the HeNB that hasreceived “eNB Configuration Update FAILURE” may retransmit the same datafrom the MTCD, without newly providing the parameter indicating that thedata has not been correctly received.

While the present modification has mainly described the example incombination with the first embodiment, the present modification can beused also in combination with the first modification of the firstembodiment, the second modification of the first embodiment, the thirdmodification of the first embodiment, and the fourth modification of thefirst embodiment.

The present modification can also be used when an eNB holds back andaggregates the signaling messages common to the MTCD group, which isdisclosed in Non-Patent Document 9.

The second modification of the second embodiment can achieve thefollowing effects in addition to the effects in the second embodiment.The present modification is more advantageous than the second embodimentand the first modification of the second embodiment in that signalingdoes not need to be newly provided, which prevents a mobilecommunication system from becoming complicated.

Third Modification of Second Embodiment

A third modification of the second embodiment discloses another specificexample of the second embodiment when the HeNB transmits the data froman MTCD being served thereby to an MME, SGSN, MTC server, or the likebeing a core network via the MME by means of the S1 interface. Theexisting S1 signaling or S1 message is used. The existing S1 signalingfor control may be used. Alternatively, the existing S1 signalingassociated with a user equipment may be used. The existing S1 signalingassociated with a user equipment is also referred to as “UE associatedSignalling” (see Non-Patent Document 14).

The following nine (1) to (9) are disclosed as specific examples of theparameters required for the existing S1 signaling when a HeNB transmitsthe data from an MTCD being served thereby to an MME, SGSN, MTC server,or the like being a core network via the MME by means of the S1interface.

(1) HeNB identity. This may be a physical cell identity (PCI), cellglobal identity (CGI), or the like for allowing a receiver to identifyvia which HeNB the data has been transmitted.

(2) MTCD identity. This may be an IMSI or a production number of an MTCDfor allowing a receiver to identify from which MTCD the data has beentransmitted. This parameter may be provided for the number of MTCDs onwhich the concentration process is performed, that is, for the samenumber as the number of MTCDs on which the concentration process isperformed.

(3) PDU for MTC. The PDU is an aggregation of pieces of data meaningfulbetween peer layers. The use of PDU enables to map, to S1 signaling tobe newly provided, data from an MTCD to a core network. This parametermay be provided for the number of MTCDs on which the concentrationprocess is performed, that is, for the same number as the number ofMTCDs on which the concentration process is performed.

(4) SDU for MTC. The SDU is an aggregation of pieces of data requestedto be transferred from upper layers. The use of SDU enables to map, toS1 signaling to be newly provided, the data from the MTCD to the corenetwork. This parameter may be provided for the number of MTCDs on whichthe concentration process is performed, that is, for the same number asthe number of MTCDs on which the concentration process is performed.

(5) Indicator indicating that S1 signaling is for MTC or indicatorindicating that S1 signaling is not associated with a normal UE. Theexistence of this parameter allows a HeNB to judge whether or not S1signaling is used for the data transmission from an MTCD being servedthereby to a core network. This eliminates the need to include theparameter regarding a normal UE during S1 signaling or enables theoperation such as indicating that a parameter regarding a normal UE ismeaningless information when the data is transmitted from an MTCD to acore network.

(6) Service type or service identity. This enables to support a case inwhich the transmission destination of data differs among services.Further, even in a case of supporting a plurality of services by oneMTCD, it is possible to support, for example, a case in which thetransmission destination of data differs among services.

(7) Information indicating to which MTC server the data is directed orto which MTC user the data is directed. Specific examples thereofinclude an MTC server identity and an MTC user identity. This enables toappropriately change the transmission destination.

(8) Identity or index indicating the combination of (6) and (7) above.

(9) Combination of (1) to (8) above.

Next, the following two (a) and (b) are disclosed as specific examplesof the existing S1 signaling.

(a) “Initial UE Message” (see Non-Patent Document 14). In the currentspecifications, when receiving an uplink NAS message, an eNB transmitsthe message to an MME with the use of “Initial UE Message” including thePDU of NAS. Therefore, the transmission of, by a HeNB, the data from anMTCD being served thereby to a core network to an MME using “Initial UEMessage” means that S1 signaling similar to the current specificationscan be used for a similar purpose. This enables to prevent a mobilecommunication system from becoming complicated. Note that the presentmodification can be used also in a case where a HeNB does not receive anuplink NAS message.

Next, parameters required to be added to and changed in “Initial UEMessage” are described. The parameters mapped to “Initial UE Message”contain “CGI” being (1) HeNB identity. Therefore, specific examples ofthe parameters required to be newly added to “Initial UE Message” are(2) to (8) below. (2) MTCD identity. (3) PDU for MTC. (4) SDU for MTC.“Initial UE Message” contains NAS-PDU. For example, if S1 signaling isfor MTC, the NAS-PDU may be a PDU for MTC. (5) Indicator indicating thatS1 signaling is for MTC. (6) Service type or service identity. (7)Information indicating to which MTC server the data is directed or towhich MTC user the data is directed. (8) Identity or index indicatingthe combination of (6) and (7) above.

The parameter required to be changed in the parameter included in“Initial UE Message” is “eNB UE S1AP ID”. In the current specifications,an eNB allocates unique “eNB UE S1AP ID” to be used for a user equipmentand maps “eNB UE S1AP ID” to “Initial UE Message”. “eNB UE S1AP ID” is aunique identity associated with a user equipment on an S1 interface. Ina case where a HeNB performs the concentration process and then the HeNBtransmits the data to a core network, the data to be transmittedincludes the data from a plurality of MTCDs in some cases. That is, theS1 interface is not used uniquely to a user equipment. This leads to asituation in which a HeNB cannot allocate “eNB UE S1AP ID”. In thecurrent specifications, “eNB UE S1AP ID” needs to be always mapped to“Initial UE Message”. That is, in a case where the data from a pluralityof MTCDs is transmitted through one “Initial UE Message” in theconcentration process, a problem that unity is lost as a mobilecommunication system arises in handling “eNB UE S1AP ID”. If unity isnot achieved as a mobile communication system, a problem that, forexample, a stable communication network cannot be provided occurs.Therefore, for example, even if “eNB UE S1AP ID” is mapped, parametersineffective in a receiver or mapping in a transmitter is not necessarilyrequired but optionally required as long as S1 signaling is for MTC.This clarifies the process by a HeNB and enables to construct a unifiedmobile communication network, and hence, a stable communication networkcan be provided.

(b) “Uplink NAS Transport” (see Non-Patent Document 14). In the currentspecifications, when receiving an NAS message to be transmitted to theMME to which a connection associated with a user equipment via S1interface exists, an eNB transmits this message to the MME with the useof “Uplink NAS Transport” including the PDU of NAS. Therefore, thetransmission of, by a HeNB, the data from an MTCD being served therebyto a core network to an MME using “Uplink NAS Transport” means that S1signaling similar to the current specifications can be used for asimilar purpose. This enables to prevent a mobile communication systemfrom becoming complicated. Note that the present modification can beused also in a case where a HeNB does not receive an uplink NAS message.Further, the present modification can be used also in a case where thereis no connection by means of the S1 interface.

Next, parameters required to be added to and changed in “Uplink NASTransport” are described. The parameters mapped to “Uplink NASTransport” contain “CGI” being (1) HeNB identity. Therefore, specificexamples of the parameters required to be newly added to “Uplink NASTransport” are (2) to (8) below. (2) MTCD identity. (3) PDU for MTC. (4)SDU for MTC. “Uplink NAS Transport” contains NAS-PDU. For example, if S1signaling is for MTC, the NAS-PDU may be a PDU for MTC. (5) Indicatorindicating that S1 signaling is for MTC. (6) Service type or serviceidentity. (7) Information indicating to which MTC server the data isdirected or to which MTC user the data is directed. (8) Identity orindex indicating the combination of (6) and (7) above.

The following two (b1) and (b2) are disclosed as the parameters thatneed to be changed in the parameters included in “Uplink NAS Transport”.

(b1) “eNB UE S1AP ID”. In the current specifications, an eNB allocatesunique “eNB UE S1AP ID” to be used for a user equipment and maps “eNB UES1AP ID” to “Uplink NAS Transport”. “eNB UE S1AP ID” is a uniqueidentity associated with the user equipment on an S1 interface. In acase where a HeNB performs the concentration process and then the HeNBtransmits the data to a core network, the data to be transmittedincludes the data from a plurality of MTCDs in some cases. That is, theS1 interface is not used uniquely to a user equipment. This leads to asituation in which a HeNB cannot allocate “eNB UE S1AP ID”.

In the current specifications, “eNB UE S1AP ID” is necessarily requiredto be mapped to “Uplink NAS Transport”. That is, in a case where thedata from a plurality of MTCDs is transmitted through one “Uplink NASTransport” in the concentration process, a problem that unity is lost asa mobile communication system occurs in handling “eNB UE S1AP ID”. Ifunity is not achieved as a mobile communication system, a problem that,for example, a stable communication network cannot be provided occurs.Therefore, for example, even if “eNB UE S1AP ID” is mapped, parametersineffective in a receiver or mapping in a transmitter is not necessarilyrequired but optionally required as long as S1 signaling is for MTC.This clarifies the process by a HeNB and enables to construct a unifiedmobile communication network, and hence, a stable communication networkcan be provided.

(b2) “MME UE S1AP ID”. “MME UE S1AP ID” is a unique identity associatedwith a user equipment on an S1 interface. In a case where a HeNBperforms the concentration process and then the HeNB transmits the datato a core network, the data to be transmitted includes the data from aplurality of MTCDs in some cases. That is, the S1 interface is not useduniquely to a user equipment. This leads to a situation in which a HeNBcannot allocate “MME UE S1AP ID”.

In the current specifications, “MME UE S1AP ID” is necessarily requiredto be mapped to “Uplink NAS Transport”. That is, in a case where thedata from a plurality of MTCDs is transmitted through one “Uplink NASTransport” in the concentration process, a problem that unity is lost asa mobile communication system occurs in handling “MME UE S1AP ID”. Ifunity is not achieved as a mobile communication system, a problem that,for example, a stable communication network cannot be provided occurs.Therefore, for example, even if “MME UE S1AP ID” is mapped, parametersineffective in a receiver or mapping in a transmitter is not necessarilyrequired but optionally required as long as S1 signaling is for MTC.This clarifies the process by a HeNB and enables to construct a unifiedmobile communication network, and hence, a stable communication networkcan be provided.

While the present modification has mainly described the example incombination with the first embodiment, the present modification can beused also in combination with the first modification of the firstembodiment, the second modification of the first embodiment, the thirdmodification of the first embodiment, and the fourth modification of thefirst embodiment.

The present modification can also be used when an eNB holds back andaggregates the signaling messages common to the MTCD group, which isdisclosed in Non-Patent Document 9.

The third modification of the second embodiment can achieve thefollowing effects in addition to the effects of the second embodiment.The present modification is more advantageous than the second embodimentand the first modification of the second embodiment in that signalingdoes not need to be newly provided, which prevents a mobilecommunication system from becoming complicated.

Fourth Modification of Second Embodiment

In a case where the second embodiment above is used, the followingproblem occurs. Considered here is the case in which a HeNB with thecapability of performing a concentration process and a HeNB without thecapability of performing a concentration process are located. It isuseless to execute the process of the second embodiment on a HeNBwithout the capability of performing a concentration process by an MME,SGSN, or the like being a core network to notify a time, a period, orresources in which communication for MTCD is allowed by means of an S1interface. Specifically, unused communication resources from the corenetwork to the HeNB and the unnecessary process by the core network aregenerated.

A solution in the fourth modification of the second embodiment isdescribed below. A portion different from the solutions of the firstembodiment and the second embodiment is mainly described. A portion thatis not described here is as in the first embodiment and the secondembodiment.

A HeNB notifies an MME, SGSN, or the like being a core network of thecapability information regarding the concentration process for the datafrom an MTCD. The core network executes the second embodiment on a HeNBwith the capability of performing a concentration process for the datafrom the MTCD, to thereby notify the HeNB of the resources for MTCD.

The core network may execute the second embodiment on only the HeNB onwhich the concentration process is performed, to thereby notify the HeNBof the resources for MTCD.

In a case of executing the second modification of the first embodiment,a core network may notify the resources for MTCD when instructing a HeNBto start the concentration process. In that case, the core network maynotify the resources for MTCD together with the instruction forconcentration ON. The resources for MTCD may be added to parameters as aspecific example of the signaling for a core network to instruct a HeNBabout concentration ON, which has been disclosed in the secondmodification of the first embodiment.

A specific example of the capability information regarding theconcentration process notified a core network by a HeNB is similar tothat of the third modification of the first embodiment, which is notdescribed here.

The following five (1) to (5) are disclosed as specific examples of thetiming at which a HeNB notifies a core network of the capabilityinformation regarding the concentration process.

(1) Time when a HeNB is installed. In a case where the capability of aHeNB to perform a concentration process remains unchanged, such aneffect that the generation of unused communication resources isprevented can be achieved.

(2) Periodically. This is effective in a case where the capability of aHeNB to perform a concentration process changes. In addition, thecapability information is notified periodically, leading to an effect ofhigh resistance to communication error.

(3) Time when the capability of a HeNB changes. This is effective in acase in which the capability of a HeNB to perform a concentrationprocess changes. Contrary to the specific example (2), notification ismade only when the capability changes in the specific example (3),whereby an effect that the generation of unused communication resourcesis prevented can be achieved.

(4) Time when a HeNB starts a concentration process or before HeNBstarts the a concentration process. It may be notified that theconcentration process is started as the capability information regardingthe concentration process. If even a HeNB with the capability ofperforming a concentration process has no MTCD being served thereby, thenotification of the resources for MTCD by a core network is unnecessary.Contrary to the specific examples (1) to (3), in the specific example(4), a core network is capable of notifying only a HeNB that actuallyneeds the resources for MTCD of the resources for MTCD. Accordingly, inthe specific example (4), the communication resources from a corenetwork to a HeNB can be used effectively, and the processing load ofthe core network can be reduced.

(5) At the end of the concentration process. It may be notified that theconcentration process is ended as the capability information regardingthe concentration process. The specific example (4) and the specificexample (5) may be used in combination.

A specific example of signaling when a HeNB notifies a core network ofthe capability information regarding the concentration process issimilar to that of the third modification of the first embodiment, whichis not described here. On that occasion, in a case where S1 signalingthat requires a response message is provided with the use of thespecific example (2), the resources for MTCD may be mapped to theresponse message. This enables to omit the communication procedure andreduce the processing loads of a HeNB and a core network. Besides, thecommunication resources can be used effectively.

In a case where the existing S1 signaling that needs the existingresponse message is provided with the use of the specific example (3),the resources for MTCD may be mapped to the response message. Thisenables to omit the communication procedure and reduce the processingloads of a HeNB and a core network. Besides, the communication resourcescan be used effectively. Specific examples of the response messageinclude “S1 SETUP RESPONSE”, “S1 SETUP FAILURE”, “eNB CONFIGURATIONUPDATE ACKNOWLEDGE”, and “eNB Configuration Update FAILURE”.

The following three (1) to (3) are disclosed as specific examples of themethod of releasing the resources for MTCD. (1) An effective period ispredetermined as to the resources for MTCD. In a case where theeffective period has elapsed, a core network releases the resources forMTCD. (2) In a case of notifying a HeNB of the resources for MTCD, acore network also notifies the effective period as to the resources. Ina case where the effective period has elapsed, a core network releasesthe resources for MTCD. (3) In a case of using the above-mentionedspecific example (5) of the timing at which a HeNB notifies a corenetwork of the capability information regarding a concentration process,the core network that has received the notification releases theresources for MTCD.

It is not required to secure unused resources by releasing the resourcesfor MTCD with the use of the specific examples (1) to (3). Further, thereleased communication resources can be used for other communication,for example, communication for normal UEs. This enables to effectivelyuse communication resources.

As to the specific examples (1) and (2), such a case is conceivable thatthe effective period may elapse also while a HeNB is performing theconcentration process and the resources for MTCD may be released by acore network. Accordingly, a HeNB may be configured to request theresources for MTCD. The specific example of signaling when a HeNBnotifies a core network of the capability information regarding aconcentration process, which has been disclosed in the thirdmodification of the first embodiment, can be used as a specific exampleof signaling when a HeNB notifies a core network of the information forrequesting the resources for MTCD, which is not described here.

A specific operation example using the fourth modification of the secondembodiment is described with reference to FIG. 25. FIG. 25 is a diagramshowing a sequence of a mobile communication system in the fourthmodification of the second embodiment. The steps of FIG. 25corresponding to the steps shown in FIG. 17, FIG. 20, and FIG. 22 aredenoted by the same reference symbols, and the common description is notgiven here.

This operation example discloses a time when a HeNB is installed, as aspecific example of the timing at which a HeNB notifies a core networkof the capability information regarding a concentration process. TheHeNB has the concentration processing capability. The case in which “S1SETUP REQUEST” being the existing S1 signaling is used is disclosed as aspecific example of signaling when a HeNB notifies a core network of thecapability information regarding the concentration process. Alsodisclosed here is the case in which the resources for MTCD are notifiedthrough “S1 SETUP RESPONSE” being a response message in response to “S1SETUP REQUEST” assuming that the “S1 SETUP” procedure has succeeded.

In Step ST2001, a HeNB is installed. In Step ST2501, the HeNB notifiesan MME of the capability information regarding the concentration processof the HeNB. “S1 SETUP REQUEST” is used in this notification. Thecapability information regarding the concentration process is mapped asa parameter of “S1 SETUP REQUEST”.

In Step ST2003, the MME judges whether or not a HeNB has the capabilityof performing a concentration process based on the capabilityinformation regarding a concentration process that has been received inStep ST2501. In a case of judging that the HeNB has the capability ofperforming a concentration process, the MME moves to Step ST2502. In acase of judging that the HeNB does not have the capability of performinga concentration process, the MME moves to Step ST2503. The HeNB has theconcentration processing capability in this operation example, and thus,the HeNB is judged to have the capability of performing a concentrationprocess, and the MME moves to Step ST2502.

In Step ST2502, the MME notifies the HeNB of the resources for MTCD. “S1SETUP RESPONSE” is used in this notification. The resources for MTCD aremapped as parameters of “S1 SETUP RESPONSE”.

In Step ST2503, the MME notifies the HeNB of “S1 SETUP RESPONSE”. Theresources for MTCD are not mapped as parameters of “S1 SETUP RESPONSE”.That is, “S1 SETUP RESPONSE” notified the HeNB in Step ST2503 does notinclude the resources for MTCD.

Then, in Step ST1703, the MTCD_1 performs the process of transmitting“RRC Connection Request” to the HeNB and, in Step ST1704, the MTCD_nperforms the process of transmitting “RRC Connection Request” to theHeNB. The HeNB that has received “RRC Connection Requests” transmittedfrom the MTCD_1 and MTCD_n performs the processes of Step ST1705 andStep ST1903 described above. After ending the process of Step ST1903,the HeNB moves to Step ST2504.

In Step ST2504, the HeNB judges whether or not the resources are theresources ones for MTCD received in Step ST2502. In a case of judgingthat the resources are ones for MTCD, the HeNB moves to Step ST2203 andthe HeNB transmits, to the MME, the data from an MTCD being servedthereby to a core network by means of an S1 interface. In a case ofjudging that the resources are not ones for MTCD, the HeNB repeats thejudgment process of Step ST2504.

While the present modification has mainly described the example incombination with the first embodiment and the second embodiment, thepresent modification can be used also in combination with the firstmodification of the first embodiment, the second modification of thefirst embodiment, the third modification of the first embodiment, thefourth modification of the first embodiment, the first modification ofthe second embodiment, the second modification of the second embodiment,and the third modification of the second embodiment.

The present modification can also be used when an eNB holds back andaggregates the signaling messages common to the MTCD group, which isdisclosed in Non-Patent Document 10.

The fourth modification of the second embodiment can achieve thefollowing effects in addition to the effects of the second embodiment.It is possible to prevent a core network from notifying a HeNB withoutthe capability of performing a concentration process of the resourcesfor MTCD. This enables to effectively use the communication resourcesfrom a core network to a HeNB and reduce the processing load of the corenetwork.

Third Embodiment

A third embodiment discloses the paging method in a case of executingthe first embodiment. The third embodiment discloses a case in which amobile communication system standardized by 3GPP is used as thecommunication method between the HeNB and MTCD.

A specific operation example using the third embodiment is describedwith reference to FIG. 26. FIG. 26 is a diagram showing a sequence of amobile communication system in the third embodiment. The steps of FIG.26 corresponding to the steps shown in FIG. 17 are denoted by the samereference symbols, and the common description is not given here.

This operation example discloses a case of NAS signaling as a specificexample of the data from an MTCD, on which a HeNB performs aconcentration process, to a core network. A case where an MTCD indicatoris mapped to the RRC message “RRC Connection Request” is disclosed as aspecific example of the method in which a HeNB distinguishes whether auser equipment (UE) being served thereby is an MTCD or not an MTCD.

First, in Step ST1703, the MTCD_1 performs the process of transmitting“RRC Connection Request” to the HeNB and, in Step ST1704, the MTCD_nperforms the process of transmitting “RRC Connection Request” to theHeNB. The HeNB that has received “RRC Connection Requests” transmittedfrom the MTCD_1 and MTCD_n performs the processes of Step ST1705 andStep ST1707 described above. The HeNB moves to Step ST2601 after endingthe process of Step ST1707.

The processes corresponding to those of Step ST1705, Step ST1707, andStep ST2202 are performed after the process of Step ST1703 in thisoperation example, which are not described here for easy understanding.

In a case of judging that the data is not from the MTCD in Step ST1705,the HeNB ends the process, which is not essential in the presentembodiment and thus is not described here.

In Step ST2601, the MTCD_1 transmits an attach message containing theidentity of the MTCD_1 to the HeNB. Non-Patent Document 13 discloses adetailed attaching method. In Step ST2602, the MTCD_n transmits anattach message containing the identity of the MTCD_n to the HeNB.

In Step ST2603, the HeNB performs the concentration process on theattach message from the MTCD_1, which has been received in Step ST2601,and the attach message from the MTCD_n, which has been received in StepST2602. In this operation example, as the concentration process, theHeNB collectively notifies the MME of the attach messages being the datafrom a plurality of MTCDs to a core network.

In Step ST2604, the HeNB notifies the MME of the attach messagesconcentrated through the concentration process in Step ST2603. Theattach message contains the identity of the MTCD_1 and the identity ofthe MTCD_n, which are identities of the MTCDs being targets of theconcentration process, the identity of the HeNB, and the TAI. The secondembodiment, the first modification of the second embodiment, the secondmodification of the second embodiment, and the third modification of thesecond embodiment can be used as the method of notifying an attachmessage.

In Step ST2605, the MME notifies a home subscriber server (HSS) of theidentity of the MTCD_1 and the identity of the MTCD_n being identitiesof the MTCDs, which have been received as attach messages. The HSS is asubscriber information database in a 3GPP mobile communication network,which is an entity that manages the authentication information and userlocation information.

In Step ST2606, the HSS registers and manages the identity of the MTCD_1and the identity of the MTCD_n being identities of the MTCDs, which havebeen attached.

In Step ST2607, the MME receives an incoming call directed to theMTCD_1. Non-Patent Document 13 and Non-Patent Document 14 disclose thedetailed method regarding an incoming call. The incoming call includesthe identity of the MTCD_1. This allows an incoming call directed to theMTCD_1 alone.

In Step ST2608, the MME searches a tracking area list (also referred toas “TAI list”) of the MTCD_1.

In Step ST2609, the MME notifies the HeNB of paging directed to theMTCD_1. Paging includes the tracking area list of the MTCD_1 and theidentity of the MTCD_1. An incoming call can be directed to the MTCD_1alone because paging includes the identity of the MTCD_1.

In Step ST2610, the HeNB judges whether or not the tracking areaincluded in the tracking area list (TAI list) of the MTCD_1, which iscontained in the paging received in Step ST2609, includes the own HeNB.In a case of judging that the own HeNB is included, the HeNB moves toStep ST2611. In a case of judging that the own HeNB is not included, theHeNB does not perform the process of Step ST2611.

In Step ST2611, the HeNB notifies the paging directed to the MTCD_1. Thepaging is notified in the mobile communication system standardized by3GPP. Specifically, the paging message is mapped to the PCCH being alogical channel, the PCCH is mapped to the PCH being a transportchannel, and the PCH is mapped to the PDSCH being a physical channel.The paging indicator common to all user equipments is transmitted overthe PDCCH. The resources of the PDSCH to which the paging message hasbeen mapped is allocated over the PDCCH over which the paging indicatorhas been transmitted. Non-Patent Document 1, Non-Patent Document 2, andNon-Patent Document 16 disclose a detailed paging notification method.

While the present modification has mainly described the example incombination with the first embodiment, the second embodiment, the firstmodification of the second embodiment, the second modification of thesecond embodiment, and the third modification of the second embodiment,the present modification can be used also in combination with the firstmodification of the first embodiment, the second modification of thefirst embodiment, the third modification of the first embodiment, andthe fourth modification of the second embodiment.

The third embodiment has disclosed the paging method in which the firstembodiment is executed and a mobile communication system standardized by3GPP is used as the communication method between the HeNB and MTCD. Theexecution of the third embodiment enables to realize paging in a casewhere a mobile communication system standardized by 3GPP is used.

Fourth Embodiment

A fourth embodiment discloses the paging method in a case where thefirst embodiment is executed. The fourth embodiment discloses the casein which a communication system other than the mobile communicationsystem standardized by 3GPP is used as the communication method betweenthe HeNB and MTCD.

A solution in the fourth embodiment is described below. A portiondifferent from the first embodiment is mainly described. A portion thatis not described here is as in the first embodiment.

The HeNB performs the concentration process on the data from an MTCDthat has made access in a communication system other than the mobilecommunication system standardized by 3GPP, and notifies an MME, SGSN,MTC server, or the like being a core network by means of the protocol ofthe mobile communication system standardized by 3GPP. The HeNB storesthe identity of the MTCD on which the concentration process has beenperformed, and when receiving a paging message containing the identityof the MTCD on which the concentration process has been performed fromthe MME, notifies an MTCD being served thereby of an incoming call.

The following three (1) to (3) are disclosed as specific examples of theconcentration process. (1) The protocol of the mobile communicationsystem standardized by 3GPP is applied to access in a communicationsystem other than the mobile communication system standardized by 3GPP.In a case where access has been made in a communication system otherthan the mobile communication system standardized by 3GPP, the HeNBinterprets access contents. Then, the HeNB selects the protocol in themobile communication system standardized by 3GPP, which corresponds tothe access contents, and notifies the MME, SGSN, MTC server, or the likebeing a core network of parameters required for the protocol arenotified. (2) The HeNB collectively notifies the MME of pieces of datafrom one or a plurality of MTCDs to a core network. This enables toreduce the number of communication times from the HeNB to the corenetwork, and thus, the congestion of the core network can be mitigated.(3) Combination of (1) and (2).

The following eight (a) to (h) are disclosed as specific examples of thecombination of the access contents in a communication system other thanthe mobile communication system standardized by 3GPP and the protocol ofthe mobile communication system standardized by 3GPP corresponding tothe access contents in a case where the specific example (1) describedabove is selected as a specific example of the concentration process. Inthe following description, a communication system other than the mobilecommunication system standardized by 3GPP is referred to as “outside3GPP” and the mobile communication system standardized by 3GPP isreferred to as “within 3GPP” in some cases.

(a) In a case where power ON of an MTCD is notified outside 3GPP,“Attach procedure” is selected within 3GPP. Non-Patent Document 13discloses the details of “Attach procedure”. (b) In a case where theinstallation of an MTCD is notified outside 3GPP, “Attach procedure” isselected within 3GPP. (c) In a case where the registration of thelocation of an MTCD is notified outside 3GPP, “Attach procedure” isselected within 3GPP. (d) In a case where the movement of an MTCD isnotified outside 3GPP, “Tracking Area Update procedure” is selectedwithin 3GPP. Non-Patent Document 13 discloses the details of “TrackingArea Update procedure”. (e) In a case where a communication request,calling request, or incoming call response of an MTCD is notifiedoutside 3GPP, “Service Request procedures” is selected within 3GPP.Non-Patent Document 13 discloses the details of “Service Requestprocedures”. (f) In a case where power OFF of an MTCD is notifiedoutside 3GPP, “Detach procedure” is selected within 3GPP. Non-PatentDocument 13 discloses the details of “Detach procedure”. (g) In a casewhere an installation cancellation of an MTCD is notified outside 3GPP,“Detach procedure” is selected within 3GPP. (h) In a case where afailure of an MTCD is notified outside 3GPP, “Detach procedure” isselected within 3GPP.

As to specific examples of the concentration process, the following four(a) to (d) are disclosed as specific examples of parameters required fora protocol when the specific example (1) above is selected.

(a) In a case of selecting “Attach procedure” within 3GPP, (a1) to (a4)below; (a1) MTCD identity, (a2) HeNB identity, (a3) tracking area ofHeNB, and (a4) combination of (a1) to (a3) above.

(b) In a case where “Tracking Area Update procedure” is selected within3GPP, (b1) to (b4) below; (b1) MTCD identity, (b2) HeNB identity, (b3)tracking area of HeNB, and (b4) combination of (b1) to (b3).

(c) In a case where “Service Request procedures” is selected, (c1) to(c4) below; (c1) MTCD identity, (c2) HeNB identity, (c3) tracking areaof HeNB, and (c4) combination of (c1) to (c3) above.

(d) In a case of selecting “Detach procedure, (d1) MTCD identity.

A specific operation example using the fourth embodiment is describedwith reference to FIG. 27. FIG. 27 is a diagram showing a sequence of amobile communication system in the fourth embodiment. The steps of FIG.27 corresponding to the steps shown in FIG. 17 and FIG. 26 are denotedby the same reference symbols, and the common description is not givenhere.

This operation example discloses a case in which the combination of thespecific example (1) and the specific example (2), which is the specificexample (3) above, is used as a specific example of the concentrationprocess. In addition, a case in which the installation of an MTCD isnotified outside 3GPP and a case in which “Attach procedure” is selectedwithin 3GPP are disclosed as a specific example of the combination ofthe access contents outside 3GPP and the protocol within 3GPPcorresponding to the access contents. Further disclosed is a case inwhich (a1) MTCD identity, (a2) HeNB identity, and (a3) tracking area ofHeNB in the specific example (a) are specific examples of the parametersrequired for “Attach procedure” when the protocol within 3GPP is appliedto access outside 3GPP.

In Step ST2701, the MTCD_1 transmits a notification of installation ofMTCD with the identity of the MTCD_1 to the HeNB.

In Step ST2702, the MTCD_n transmits a notification of MTCD installationwith the identity of the MTCD_n to the HeNB.

In Step ST2703, the HeNB checks whether or not to have received thenotification of MTCD installation with the identity of the MTCD_n inStep ST2702 outside 3GPP, and judges whether or not the notification ofMTCD installation is the data from the MTCD. In a case of judging tohave received the notification of MTCD installation with the identity ofthe MTCD outside 3GPP, the HeNB judges that the notification is the datafrom the MTCD and moves to Step ST2704. In a case of judging to not havereceived the notification of MTCD installation with the identity of theMTCD outside 3GPP, the HeNB judges that the notification is not the datafrom the MTCD and ends the process, which is not essential in thepresent embodiment and thus is not described here.

In a case of receiving the notification outside 3GPP without checkingwhether or not the MTCD identity is included, the HeNB may judge thatthe notification is the data from the MTCD and move to Step ST2704. In acase of receiving the notification within 3GPP, the HeNB may judge thatthe notification is the data from the normal UE and end the process,which is not essential in the present embodiment and thus is notdescribed here.

In Step ST2704, the HeNB stores the identities of the MTCDs on which theconcentration process is performed. In this operation example, the HeNBstores the identity of the MTCD_1 and the identity of the MTCD_n.

In Step ST2705, the HeNB performs the concentration process. In thisoperation example, the HeNB collectively notifies the MME of the piecesof data from the MTCD_1 and MTCD_n to the core network. In addition, theHeNB interprets the contents of Step ST2701 and Step ST2702 each beingaccess outside 3GPP and understands that the access is related to“installation”. Then, the HeNB selects “Attach procedure” as theprotocol within 3GPP corresponding to the access related to“installation”. Further, the HeNB maps, as parameters, the identity ofthe MTCD_1 received in Step ST2701, the identity of the MTCD_n receivedin Step ST2702, the identity of the own HeNB, and the tracking area ofthe HeNB to “Attach procedure”.

The processes corresponding to those of Step ST2703, Step ST2704, andStep ST2705 are performed after the process of Step ST2701 in thisoperation example, which are not described here for easy understanding.

In Step ST2706, the HeNB notifies the MME of the attach messageconcentrated through the concentration process in Step ST2705. Theattach message contains the identity of the MTCD_1 and the identity ofthe MTCD_n, which are identities of the MTCDs being targets of theconcentration process, the identity of the HeNB, and the TAI. The secondembodiment, the first modification of the second embodiment, the secondmodification of the second embodiment, and the third modification of thesecond embodiment can be used for this notification.

After the process of Step ST2706, the MME performs the process of StepST2605, and the HSS performs the process of Step ST2606. Then, the MMEreceives an incoming call directed to the MTCD_1 in Step ST2607, and theMME performs the processes of Step ST2608 and Step ST2609.

Then, in Step ST2707, the HeNB judges whether or not to have performedthe concentration process on the MTCD_1 included in the paging receivedin Step ST2609. The information stored in Step ST2704 may be used forthe judgment process of Step ST2707. In a case of judging to haveperformed the concentration process, the HeNB moves to Step ST2708. In acase of judging to not have performed the concentration process, theHeNB moves to Step ST2709. In this operation example, the HeNB hasperformed the concentration process on the MTCD_1, and accordingly movesto Step ST2708.

In Step ST2708, the HeNB notifies the MTCD_1 of the incoming calldirected to the MTCD_1. The HeNB notifies an incoming call in StepST2708 in a communication system other than the communication system by3GPP used in Step ST2701. In Step ST2709, the HeNB judges whether or notthe own HeNB is included in the tracking area contained in the trackingarea list of the MTCD_1 included in the paging received in Step ST2609.In a case of judging that the own HeNB is included, the HeNB moves toStep ST2710. In a case of judging that the own HeNB is not included, theHeNB does not perform the process of Step ST2710. In Step ST2710, theHeNB notifies an incoming call in the communication system within 3GPP.

While the present embodiment has mainly described the example incombination with the first embodiment, the second embodiment, the firstmodification of the second embodiment, the second modification of thesecond embodiment, and the third modification of the second embodiment,the present embodiment can be used also in combination with the firstmodification of the first embodiment, the second modification of thefirst embodiment, the third modification of the first embodiment, andthe fourth modification of the second embodiment.

While the present embodiment has described the case in which thecommunication method between the HeNB and MTCD is one outside 3GPP, thepresent embodiment can also be used in a case where the communicationmethod between the HeNB and MTCD is one within 3GPP.

The fourth embodiment described above discloses a paging method in whichthe first embodiment is executed and a communication system other thanthe mobile communication system standardized by 3GPP is used as thecommunication system between the HeNB and MTCD. The execution of thefourth embodiment enables paging in a case where a communication systemother than the mobile communication system standardized by 3GPP is used.

First Modification of Fourth Embodiment

A problem below occurs in a case where the fourth embodiment above isused. Even in a case where an MTCD moves and cannot communicate with anMTC server via a HeNB, the MTCD identity continues to be stored assumingthat this MTCD is an MTCD on which the concentration process has beenperformed by the HeNB. This causes a problem that the memory area of theHeNB is used for unnecessary data.

The following two (1) and (2) are disclosed as the solutions in a firstmodification of the fourth embodiment. (1) In a case of moving and beingunable to communicate with an MTC server via a HeNB, the MTCD notifiesthe HeNB of this. In a case of moving, the MTCD notifies a source HeNBof this. The HeNB that has received this notification deletes this MTCDfrom the memory of the MTCD on which the concentration process has beenperformed.

(2) In a case of moving and being unable to communicate with an MTCserver via a HeNB, the MTCD notifies a core network of this via theHeNB. In a case of moving, the MTCD notifies the core network of thisvia a source HeNB. The core network that has received this notificationjudges whether or not to change a source cell of the MTCD. In a case ofhaving determined to change a source cell, the core network notifies theHeNB that the source cell will be changed. The HeNB that has receivedthis notification deletes the MTCD from the memory of the MTCD on whichthe concentration process has been performed. The notificationindicating that the source cell will be changed from the core network tothe HeNB includes the MTCD identity.

The following three (1) to (3) are disclosed as specific examples of thecontents notified from an MTCD to a HeNB; (1) moving, (2) changing of aserving cell, and (3) handover.

The first modification of the fourth embodiment can achieve thefollowing effects in addition to the effects of the fourth embodiment.In a case where an MTCD moves and cannot communicate with an MTC servervia a HeNB, that is, in a case where a HeNB cannot perform theconcentration process on the MTCD, it is possible to delete the data ofthe MTCD from the memory area of the HeNB. This enables to prevent theuse of a memory area of the HeNB for unnecessary data.

Fifth Embodiment

A fifth embodiment discloses a paging method when the first embodimentis executed. The fifth embodiment discloses a paging method per HeNB,not paging per MTCD, which may be paging per HeNB on which theconcentration process has been performed.

A solution in the fifth embodiment is described below. A portiondifferent from the solution of the first embodiment is mainly described.A portion that is not described here is as in the first embodiment.

The registration with an operator or MTC user is performed on aHeNB-basis, on which the concentration process is performed, not on anMTCD-basis. To take one example of service, a contract is made as oneMTCD per HeNB installed in a building. One contract is made as a HeNBeven in a case where a plurality of MTCDs to be served by a HeNB arelocated. Registration is made with a core network on a HeNB-basis onwhich the concentration process has been performed, and paging is madeto the HeNB. The HeNB that has received the paging notifies the allMTCDs being served thereby of an incoming call.

A specific example of the concentration process is disclosed below. Theoperation of a specific example (5) below is performed together with thespecific examples (1) to (4) disclosed in the first embodiment. (5) TheMTCD identity included in the data from the MTCD being served thereby toa core network is deleted, and the identity of the own HeNB is mapped inplace of the deleted identity. In a case of a message notified to thecore network, to which the identity of the HeNB has been added, it ismerely required to delete the MTCD identity.

A specific example of the method of registering with a core network isdisclosed below. An MME notifies an HSS of the identity of a HeNB onwhich the data of the MTCD to the core network has been concentrated,not of the identity of an MTCD. The HSS registers the identity of theHeNB, on which the concentration process has been performed, not theMTCD identity.

The following two (1) and (2) are disclosed as specific examples inwhich a HeNB notifies all MTCDs being served thereby of an incomingcall; (1) broadcast information is used, and (2) group calling is used.

A specific operation example using the fifth embodiment is describedwith reference to FIG. 28. FIG. 28 is a diagram showing a sequence of amobile communication system in the fifth embodiment. The steps of FIG.28 corresponding to the steps shown in FIG. 17 and FIG. 26 are denotedby the same reference symbols, and the common description is not givenhere.

This operation example discloses a case of NAS signaling as a specificexample of the data from an MTCD, on which a HeNB performs aconcentration process, to a core network. A case in which an MTCDindicator is mapped to an RRC message “RRC Connection Request” isdisclosed as a specific example of the method in which a HeNBdistinguishes whether a user equipment (UE) being served thereby is anMTCD or not an MTCD. In addition, a case of using broadcast informationis disclosed as a specific example in which a HeNB notifies all MTCDsbeing served thereby of an incoming call.

First, the MTCD_1 performs the process of Step ST1703, and the MTCD_nperforms the process of Step ST1704. Then, a HeNB that has received “RRCConnection Requests” transmitted from the MTCD_1 and MTCD_n performs theprocesses of Step ST1705 and Step ST1707. Then, the MTCD_1 performs theprocess of Step ST2601, and the MTCD_n performs the process of StepST2602.

Then, in Step ST2801, the HeNB performs the concentration process on theattach message from the MTCD_1, which has been received in Step ST2601,and the attach message from the MTCD_n, which has been received in StepST2602. In this operation example, as the concentration process, theHeNB collectively notifies the MME of the attach messages being datafrom a plurality of MTCDs to a core network. On that occasion, the HeNBdoes not notify the MME of the identity of the MTCD_1 and the identityof the MTCD_n, which are identities of MTCDs included in the data froman MTCD being served thereby to a core network. In place of notifyingthe identity of the MTCD, the HeNB notifies the identity of the ownHeNB. Note that the identity of the own HeNB is a parameter notified in“Attach procedure” from an eNB to an MME in the current specifications(see Non-Patent Document 13). In Step ST2801 in this operation example,it suffices that the HeNB deletes only the MTCD identity from the attachmessage received from an MTCD being served thereby.

In Step ST2802, the HeNB notifies the MME of the attach messageconcentrated through the concentration process in Step ST2801. Theattach message does not contain the identity of the MTCD_1 and theidentity of the MTCD_n which are identities of MTCDs being subjects ofthe concentration process, but contains the identity of the HeNB and theTAI. The TAI is notified as required. The second embodiment, the firstmodification of the second embodiment, the second modification of thesecond embodiment, and the third modification of the second embodimentcan be used for the notification of Step ST2802.

In Step ST2803, the MME notifies the HSS of the identity of the HeNBreceived through the attach message. In Step ST2804, the HSS registersand manages the HeNB on which attaching has been performed.

In Step ST2805, the MME receives an incoming call directed to a HeNB.Non-Patent Document 13 and Non-Patent Document 14 disclose a detailedmethod regarding an incoming call. The incoming call includes theidentity of a HeNB. This enables an incoming call on a HeNB-basis.

In Step ST2806, the MME judges whether or not a HeNB to be served by theown MME is located. The MME moves to Step ST2807 in a case of judgingthat a HeNB is located, or ends the process in a case of judging that aHeNB is not located. In this operation example, a HeNB to be served bythe own MME is located, and thus, the MME moves to Step ST2807. The MMEmay notify an eNB, HeNB, or the like being a base station being servedthereby of paging in Step ST2807, without performing the process of StepST2806.

In Step ST2807, the MME notifies the HeNB of paging directed to theHeNB. This paging does not include a tracking area list of the MTCD_1,an identity of the MTCD_1, and “UE Identity Index value”. A sixthembodiment below describes “UE Identity Index value”. The pagingincludes the identity of the HeNB in place of including the trackingarea list of the MTCD_1 and the identity of the MTCD_1. Inclusion of theidentity of a HeNB allows an incoming call on a HeNB-basis.

In Step ST2808, the HeNB judges whether or not the identity included inthe paging received in Step ST2807 is the identity of the HeNB. In acase of judging that the identity is that of the HeNB, the HeNB moves toStep ST2809. In a case of judging that the identity is not that of theHeNB, the HeNB judges that the identity is that of a user equipment andmoves to Step ST2610. In this operation example, the identity includedin the paging received in Step ST2807 is the identity of the HeNB, andthus moves to Step ST2809.

In Step ST2809, the HeNB judges whether or not the identity of the HeNBincluded in the paging received in Step ST2807 is the identity of theown HeNB. In a case of judging that the identity is that of the ownHeNB, the HeNB moves to Step ST2810. In a case of judging that theidentity is not that of the own HeNB, the HeNB ends the process. In thisoperation example, the identity of the HeNB included in the pagingreceived in Step ST2807 is the identity of the own HeNB, and thus, theHeNB moves to Step ST2810.

In Step ST2810, the HeNB notifies the all MTCDs being served thereby ofan incoming call through the broadcast information.

In Step ST2811, the HeNB notifies paging that includes a user equipmentidentity as usual. This paging is notified in the mobile communicationsystem standardized by 3GPP. Specifically, the paging message is mappedto the PCCH being a logical channel, the PCCH is mapped to the PCH beinga transport channel, and the PCH is mapped to the PDSCH being a physicalchannel. The paging indicator common to all user equipments istransmitted over the PDCCH. The resources of the PDSCH, on which thepaging message has been mapped, are allocated with the PDCCH on whichthe paging indicator has been transmitted. Non-Patent Document 1,Non-Patent Document 2, and Non-Patent Document 16 disclose a detailedpaging notification method.

While the present embodiment has mainly described the example incombination with the first embodiment, the second embodiment, the firstmodification of the second embodiment, the second modification of thesecond embodiment, and the third modification of the second embodiment,the present embodiment can be used also in combination with the firstmodification of the first embodiment, the second modification of thefirst embodiment, the third modification of the first embodiment, andthe fourth modification of the second embodiment.

While this embodiment has described the case in which the communicationmethod between the HeNB and MTCD is within 3GPP, the present embodimentcan be used also in a case where the communication method between theHeNB and MTCD is outside 3GPP.

The fifth embodiment has described the paging method in which the firstembodiment is executed and paging is performed per HeNB, not per MTCD.The execution of the fifth embodiment enables to realize paging perHeNB.

First Modification of Fifth Embodiment

A first modification of the fifth embodiment discloses the method inwhich the fifth embodiment is executed, and paging per MTCD is performedeven in a case in which, for example, the registration with an operatoror MTC user is made on a HeNB-basis on which the concentration processis performed, not on an MTCD-basis.

A solution in the first modification of the fifth embodiment isdescribed below. A portion different from the solutions of the firstembodiment and the fifth embodiment is mainly described. A portion thatis not described here is as in the first embodiment and the fifthembodiment.

A HeNB stores an identity of the MTCD on which the concentration processhas been performed, and notifies the MTCD being served thereby of anincoming call when receiving a paging message containing the MTCDidentity separately from the identity of the HeNB from the MME.

A specific operation example using the first modification of the fifthembodiment is described with reference to FIG. 29. FIG. 29 is a diagramshowing a sequence of a mobile communication system in the firstmodification of the fifth embodiment. The steps of FIG. 29 correspondingto the steps shown in FIG. 17, FIG. 26, and FIG. 28 are denoted by thesame reference symbols, and the common description is not given here.

This operation example discloses a case of NAS signaling as a specificexample of the data from an MTCD, on which a HeNB performs aconcentration process, to a core network. In addition, a case in whichan MTCD indicator is mapped to the RRC message “RRC Connection Request”is disclosed as a specific example of the method in which a HeNBdistinguishes whether a user equipment (UE) being served thereby is anMTCD or is not an MTCD.

First, the MTCD_1 performs the process of Step ST1703, and the MTCD_nperforms the process of Step ST1704. Then, the HeNB that has received“RRC Connection Requests” transmitted from the MTCD_1 and MTCD_nperforms the processes of Step ST1705 and Step ST1707. Then, the MTCD_1performs the process of Step ST2601, and the MTCD_n performs the processof Step ST2602. The HeNB that has received the attach messagestransmitted from the MTCD_1 and MTCD_n performs the processes of StepST2704, Step ST2801, and Step ST2802. Then, the MME performs the processof Step ST2803, and the HSS performs the process of Step ST2804.

In Step ST2901, the MME receives an incoming call directed to a HeNB.Non-Patent Document 13 and Non-Patent Document 14 disclose a detailedmethod regarding an incoming call. An incoming call includes theidentity of the MTCD_1 that is required to be called individually,separately from the identity of the HeNB. This enables to perform pagingper MTCD even in a case where the registration with an operator or thelike is performed on a HeNB-basis on which the concentration process isperformed, not on an MTCD-basis. The MME performs the process of StepST2806 after the process of Step ST2901. In Step ST2806, the MME movesto Step ST2902 in a case of judging that a HeNB to be served by the ownMME is located.

In Step ST2902, the MME notifies the HeNB of the paging directed to aHeNB. This paging includes the identity of the MTCD_1 but does notinclude the tracking area list of the MTCD_1. The HeNB performs theprocesses of Step ST2808 and Step ST2809. The HeNB moves to Step ST2903in a case of judging that the identity of the HeNB included in thepaging received in Step ST2902 is the identity of the own HeNB inST2809.

In Step ST2903, the HeNB judges whether or not to have performed theconcentration process on the MTCD_1 with the MTCD_1 identity included inthe paging received in Step ST2902. The information stored in StepST2704 may be used in the judgment of Step ST2903. In a case of judgingto have performed the concentration process, the HeNB moves to StepST2611. In a case of judging to not have performed the concentrationprocess, the HeNB ends the process.

While the present modification has mainly described the example incombination with the first embodiment, the second embodiment, the firstmodification of the second embodiment, the second modification of thesecond embodiment, and the third modification of the second embodiment,the present modification can be used also in combination with the firstmodification of the first embodiment, the second modification of thefirst embodiment, the third modification of the first embodiment, andthe fourth modification of the second embodiment.

While the present modification has described a case in which thecommunication method between the HeNB and MTCD is within 3GPP, thepresent modification can be used also in a case where the communicationmethod between the HeNB and MTCD is outside 3GPP.

The first modification of the fifth embodiment has disclosed the methodin which the fifth embodiment is executed in addition to the firstembodiment, and paging per MTCD is performed even in a case where, forexample, the registration with an operator or MTC user is performed on aHeNB-basis on which the concentration process is performed, not on anMTCD-basis. The execution of the first modification of the fifthembodiment enables to realize paging per MTCD in a case where, forexample, the registration with an operator or MTC user is performed on aHeNB-basis on which a concentration process is performed.

Sixth Embodiment

A problem to be solved by the sixth embodiment is described below. In acase of using broadcast information when a HeNB notifies all MTCDs beingserved thereby of an incoming call in the fifth embodiment, a radiointerval, that is, an interval between the HeNB and MTCD is differentfrom that in normal paging transmission. There are parameters for use insetting a radio interval in paging from the MME to the HeNB.Accordingly, there are unnecessary parameters, and thus, unusedresources are generated.

A solution in the sixth embodiment is described below. A portiondifferent from the solution of the first embodiment or the fifthembodiment is mainly described. A portion that is not described here isas in the first embodiment or the fifth embodiment.

In a case of performing paging per HeNB, not paging per MTCD, a pagingmessage from an MME to a HeNB is varied from that in the currentspecifications (see Non-Patent Document 14). In a case where a receivedincoming call includes a HeNB identity, not an MTCD identity, the pagingmessage from the MME to the HeNB is varied from that in the currentspecifications.

The following two (1) and (2) are disclosed as specific examples of thepaging message varied from that in the current specifications.

(1) A new paging message on a HeNB-basis is provided. Alternatively, apaging message in a case where a new concentration process is performedis provided. Specific examples of the parameter contained in the newmessage include the HeNB identity.

(2) “Paging” being the existing S1 signaling is used in paging on aHeNB-basis. “Paging” being the existing S1 signaling is used in pagingin a case where a concentration process is performed.

Next, the parameters needed to be added to and changed in “Paging” aredescribed. The specific examples of the parameters needed to be addedinclude the HeNB identity. The following three (a) to (c) are disclosedas the specific examples of the parameters need to be changed.

(a) “UE Identity Index value”. In the current specifications, “UEIdentity Index value” is used for calculating “Paging Frame (PF)” beinga radio frame for use in the transmission of paging by an eNB. In a casewhere a HeNB notifies an MTCD being served thereby of an incoming callthrough broadcast information, the HeNB does not need to calculate aradio frame for use in the transmission of paging. This causes asituation in which “UE Identity Index value” cannot be designated in amobile communication system. In addition, in the current specifications,it is always required to map “UE Identity Index value” to “Paging”. Thatis, in a case where not paging per MTCD but paging per HeNB istransmitted through the current “Paging”, a problem that unity is lostas a mobile communication system occurs in handling “UE Identity Indexvalue”. If unity is not achieved as a mobile communication system, aproblem that, for example, a stable communication network cannot beprovided arises. Therefore, as long as the HeNB identity is mapped to,for example, “Paging”, it is judged that the paging is per HeNB. Then,if “UE Identity Index value” has been mapped, it is treated as anineffective parameter by a receiver or is not necessarily but optionallymapped by a transmitter. This clarifies the processes by an MME and aHeNB and enables to construct a unified mobile communication network,and hence, a stable communication network can be provided.

(b) “UE Paging Identity”. In the current specifications, “UE PagingIdentity” is an identity of a user equipment to be called. In a casewhere a HeNB notifies all MTCDs being served thereby of an incoming callthrough the broadcast information, the HeNB does not require a dedicatedidentity of an MTCD, which is one type of user equipment. It is alsoassumed that a dedicated identity of an MTCD is not notified also from acaller. This causes a situation in which “UE Paging Identity” cannot bedesignated in a mobile communication system. In the currentspecifications, it is always required to map “UE Paging Identity” to“Paging”. That is, in a case where not paging per MTCD but paging perHeNB is transmitted through the current “Paging”, a problem that unityis lost as a mobile communication system occurs in handling “UE PagingIdentity”. If unity is not achieved as a mobile communication system,such a problem arises that a stable communication network cannot beprovided. Therefore, if the identity of the HeNB is mapped to, forexample, “Paging”, it is judged that paging is per HeNB. Then, even if“UE Paging Identity” has been mapped, it is treated as an ineffectiveparameter by a receiver or is not necessarily but optionally mapped by atransmitter. This clarifies the processes by an MME and a HeNB andenables to construct a unified mobile communication network, and hence,a stable communication network can be provided.

(c) “TA information”. In the current specifications, as to “TAinformation”, an eNB belonging to the TA information transmits paging.In a case where a HeNB notifies an MTCD being served thereby of anincoming call through the broadcast information, the paging includes theHeNB identity. This may allow a HeNB with the identity matching theidentity of the HeNB included in paging to notify an MTCD being servedthereby of an incoming call. Therefore, “TA information” is a parameterthat is not particularly needed. Meanwhile, in the currentspecifications, it is required to necessarily map “TA information” to“Paging”. That is, in a case where not paging per MTCD but paging perHeNB is transmitted through the current “Paging”, “TA information” beingan unnecessary parameter is notified. Hence, if the HeNB identity ismapped to, for example, “Paging”, it is judged that paging is per HeNBand “TA information” is not necessarily but optionally mapped by atransmitter. This enables to prevent the transmission of unnecessaryparameters.

The sixth embodiment can achieve the following effects in addition tothe effects of the fifth embodiment. Unnecessary parameters in pagingfrom an MME to a HeNB can be reduced, and thus, resources can be usedeffectively.

Seventh Embodiment

A problem to be solved by a seventh embodiment is described below.First, the current paging method is described. Non-Patent Document 14discloses the following. In each cell belonging to a tracking area shownin a TAI list contained in a paging message notified an eNB by an MME,paging occurs on a radio interface.

The current paging method is described again with reference to FIG. 30.FIG. 30 is a diagram showing the location for describing the currentpaging method. First, the location of FIG. 30 is described. An eNB 3001,a HeNB 3003, a HeNB 3005, and a HeNB 3007 are installed. The eNB 3001has a coverage 3002. The HeNB 3003 has a coverage 3004. The HeNB 3005has a coverage 3006. The HeNB 3007 has a coverage 3008. A user equipment3009 is located within the coverage 3008 of the HeNB 3007. The eNB 3001,HeNB 3003, HeNB 3005, and HeNB 3007 are located within the coverage 3002of the eNB 3001. The eNB 3001, HeNB 3003, HeNB 3005, and HeNB 3007 areincluded in a tracking area #1 (TA #1) 3016.

An eNB 3010, a HeNB 3012, and a HeNB 3014 are installed. The eNB 3010has a coverage 3011. The HeNB 3012 has a coverage 3013. The HeNB 3014has a coverage 3015. The eNB 3010, HeNB 3012, and HeNB 3014 are locatedwithin the coverage 3011 of the eNB 3010. The eNB 3010, HeNB 3012, andHeNB 3014 are included in a tracking area #2 (TA #2) 3017.

Considered here is a case in which the tracking area #1 (TA #1) 3016 andthe tracking area #2 (TA #2) 3017 are registered as a tracking area listof the user equipment 3009. The current paging method in a case where anincoming call to the user equipment 3009 is made in the location isdescribed.

In the current specifications, in each cell belonging to a tracking areashown in a TAI list contained in a paging message notified an eNB by anMME, paging occurs on a radio interface. Therefore, paging occurs on aradio interface from the eNB 3001, HeNB 3003, HeNB 3005, and HeNB 3007belonging to the tracking area #1 (TA #1) 3016 and the eNB 3010, HeNB3012, and HeNB 3014 belonging to the tracking area #2 (TA #2) 3017.Meaningless paging transmission has conventional problems that radioresources cannot be used effectively and that interference occurs.

Next, the problem to be solved in the seventh embodiment is describedbelow. Considered here is a case in which a HeNB with the capability ofperforming a concentration process and a HeNB without the capability ofperforming a concentration process are located. In a case where thethird embodiment and fourth embodiment above are executed, thenotification of paging or notification of an incoming call from a HeNBwithout the concentration processing capability to an MTCD becomesunnecessary. This causes a problem that radio resources cannot be usedeffectively.

Unused radio resources in a case of executing the third embodiment aboveare described with reference to FIG. 31 and FIG. 32. FIG. 31 and FIG. 32are diagrams showing a sequence of a mobile communication system fordescribing the unused radio resources in the case where the thirdembodiment is executed. FIG. 31 and FIG. 32 are continuous from eachother at a position of a boundary A1. The steps of FIG. 31 and FIG. 32corresponding to the steps shown in FIG. 17 and FIG. 26 are denoted bythe same reference symbols, and the common description is not givenhere.

In this operation example, description is given with reference to thelocation diagram shown in FIG. 30. The HeNB 3003 and HeNB 3007 are HeNBswith the capability of performing a concentration process, and the HeNB3005 is a HeNB without the capability of performing a concentrationprocess. The user equipment 3009 is an MTCD, and the MTCD identity isMTCD_1.

First, the MTCD_1 performs the process of Step ST1703, and the MTCD_nperforms the process of Step ST1704. Then, the HeNB 3007 that hasreceived “RRC Connection Requests” transmitted from the MTCD_1 andMTCD_n performs the processes of Step ST1705 and Step ST1707. Then, theMTCD_1 performs the process of Step ST2601, and the MTCD_n performs theprocess of Step ST2602. Then, the HeNB 3007 that has received the attachmessages transmitted from the MTCD_1 and MTCD_n performs the processesof Step ST2603 and Step ST2604. Then, the MME performs the process ofStep ST2605. Then, the HSS performs the process of Step ST2606.

The MME receives an incoming call directed to the MTCD_1 in Step ST2607,and then, in Step ST2608, the MME searches the tracking area list (alsoreferred to as TAI list) of the MTCD_1. In this operation example, it isrevealed to the MME that the tracking area list of the MTCD_1 includesthe tracking area #1 (TA #1) 3016 and the tracking area #2 (TA #2) 3017.

In Step ST3101, the MME notifies the HeNB 3007 of paging directed to theMTCD_1. This paging includes the tracking area list of the MTCD_1 andthe identity of the MTCD_1.

In Step ST3102, the MME notifies the HeNB 3005 of paging directed to theMTCD_1. This paging includes the tracking area list of the MTCD_1 andthe identity of the MTCD_1.

In Step ST3103, the MME notifies the HeNB 3003 of paging directed to theMTCD_1. This paging includes the tracking area list of the MTCD_1 andthe identity of the MTCD_1.

In Step ST3104, the HeNB 3007 judges whether or not the tracking areaincluded in the tracking area list of the MTCD_1, which is contained inthe paging received in Step ST3101, includes the own HeNB. In a case ofjudging that the own HeNB is included, the HeNB 3007 moves to StepST3105. In a case of judging that the own HeNB is not included, the HeNB3007 does not perform the process of Step ST3105. In this operationexample, the tracking area #1 (TA #1) 3016 included in the tracking arealist includes the own HeNB 3007 as shown in FIG. 30. Accordingly, theHeNB 3007 moves to Step ST3105 after the process of Step ST3104.

In Step ST3105, the HeNB 3007 notifies the MTCD_1 of paging directed tothe MTCD_1. This paging is notified in the mobile communication systemstandardized by 3GPP. Non-Patent Document 1, Non-Patent Document 2, andNon-Patent Document 16 disclose a detailed notification method for thepaging.

In Step ST3106, the HeNB 3005 judges whether or not the tracking areaincluded in the tracking area list of the MTCD_1, which is contained inthe paging received in Step ST3102, includes the own HeNB. In a case ofjudging that the own HeNB is included, the HeNB 3005 moves to StepST3107. In a case of judging that the own HeNB is not included, the HeNB3005 does not perform the process of Step ST3107. In this operationexample, the tracking area #1 (TA #1) 3016 included in the tracking arealist includes the own HeNB 3005 as shown in FIG. 30. Accordingly, theHeNB 3005 moves to Step ST3107 after the process of Step ST3106.

In Step ST3107, the HeNB 3005 notifies paging directed to the MTCD_1.This paging is notified in the mobile communication system standardizedby 3GPP. Non-Patent Document 1, Non-Patent Document 2, and Non-PatentDocument 16 disclose a detailed notification method for the paging.

In Step ST3108, the HeNB 3003 judges whether or not the tracking areaincluded in the tracking area list of the MTCD_1, which is contained inthe paging received in Step ST3103, includes the own HeNB. In a case ofjudging that the own HeNB is included, the HeNB 3003 moves to StepST3109. In a case of judging that the own HeNB is not included, the HeNB3003 does not perform the process of Step ST3109. In this operationexample, the tracking area #1 (TA #1) 3016 included in the tracking arealist includes the own HeNB 3003 as shown in FIG. 30. Therefore, the HeNB3003 moves to Step ST3109 after the process of Step ST3108.

In Step ST3109, the HeNB 3003 notifies paging directed to the MTCD_1.This paging is notified in the mobile communication system standardizedby 3GPP. Non-Patent Document 1, Non-Patent Document 2, and Non-PatentDocument 16 disclose a detailed notification method for the paging.

As described above, the user equipment 3009 whose MTCD identity isMTCD_1 is located within the coverage 3008 of the HeNB 3007, and thusreceives paging from the HeNB 3007 in Step ST3105. Therefore, the pagingfrom the HeNB 3005 in Step ST3107 and the paging from the HeNB 3003 inStep ST3109 become unnecessary.

Next, unused radio resources in a case where the fourth embodiment isexecuted are described with reference to FIG. 33 and FIG. 34. FIG. 33and FIG. 34 are diagrams showing a sequence of a mobile communicationsystem for describing the unused radio resources in the case where thefourth embodiment is executed. FIG. 33 and FIG. 34 are continuous fromeach other at a position of a boundary A2. The steps of FIG. 33 and FIG.34 corresponding to the steps shown in FIG. 26, FIG. 27, FIG. 31, andFIG. 32 are denoted by the same reference symbols, and the commondescription is not given here.

In this operation example, description is given with reference to thelocation diagram shown in FIG. 30. The HeNB 3003 and the HeNB 3007 areHeNBs with the capability of performing a concentration process, and theHeNB 3005 is a HeNB without the capability of performing a concentrationprocess. The user equipment 3009 is an MTCD, and the identity of theMTCD is MTCD_1. The HeNB 3007 concentrates the data from the userequipment 3009.

First, the MTCD_1 performs the process of Step ST2701, and the MTCD_nperforms the process of Step ST2702. Then, the HeNB 3007 performs theprocesses of Step ST2703 to Step ST2706. Then, the MME performs theprocess of Step ST2605, and the HSS performs the process of Step ST2606.

The MME receives an incoming call directed to the MTCD_1 in Step ST2607,and then, in Step ST2608, the MME searches the tracking area list (alsoreferred to as TAI list) of the MTCD_1. In this operation example, it isrevealed to the MME that the tracking area list of the MTCD_1 includesthe tracking area #1 (TA #1) 3016 and the tracking area #2 (TA #2) 3017.

In Step ST3101, the MME notifies the HeNB 3007 of the paging directed tothe MTCD_1. This paging includes the tracking area list of the MTCD_1and the identity of the MTCD_1.

In Step ST3102, the MME notifies the HeNB 3005 of paging directed to theMTCD_1. This paging includes the tracking area list of the MTCD_1 andthe identity of the MTCD_1.

In Step ST3103, the MME notifies the HeNB 3003 of the paging directed tothe MTCD_1. This paging includes the tracking area list of the MTCD_1and the identity of the MTCD_1.

The HeNB 3007 has the capability of performing a concentration process.Accordingly, in Step ST2707, the HeNB judges whether or not to haveperformed a concentration process on the MTCD_1 included in the pagingreceived in Step ST3101. The information stored in Step ST2704 may beused for the judgment process of Step ST2707. In a case of judging tohave performed the concentration process, the HeNB 3007 moves to StepST2708. In a case of judging to not have performed the concentrationprocess, the HeNB 3007 moves to Step ST2709. In this operation example,the HeNB 3007 has performed the concentration process on the MTCD_1.Accordingly, the HeNB 3007 judges to have performed the concentrationprocess and moves to Step ST2708.

The HeNB 3005 does not have the capability of performing a concentrationprocess. Accordingly, in Step ST3106, the HeNB 3005 judges whether ornot the tracking area included in the tracking area list of the MTCD_1,which is contained in the paging received in Step ST3102, includes theown HeNB as in the current paging method. In a case of judging that theown HeNB is included, the HeNB 3005 moves to Step ST3107. In a case ofjudging that the own HeNB is not included, the HeNB 3005 does notperform the process of Step ST3107. In this operation example, thetracking area #1 (TA #1) 3016 included in the tracking area listincludes the own HeNB 3005 as shown in FIG. 30. Accordingly, the HeNB3005 moves to Step ST3107 after the process of Step ST3106.

The HeNB 3003 has the capability of performing a concentration process.Accordingly, in Step ST3201, the HeNB judges whether or not to haveperformed the concentration process on the MTCD_1 included in the pagingreceived in Step ST3103. In a case of judging to have performed theconcentration process, the HeNB 3003 moves to Step ST3109. In a case ofjudging to not have performed the concentration process, the HeNB 3003moves to Step ST3202. In this operation example, the HeNB 3003 has notperformed the concentration process on the MTCD_1. Accordingly, the HeNB3003 judges not to have performed the concentration process and moves toStep ST3202.

In Step ST3202, the HeNB judges whether or not the tracking areaincluded in the tracking area list of the MTCD_1, which is contained inthe paging received in Step ST3103, includes the own HeNB. In a case ofjudging that the own HeNB is included, the HeNB moves to Step ST3203. Ina case of judging that the own HeNB is not included, the HeNB does notperform the process of Step ST3203. In Step ST3203, the HeNB notifies anincoming call in the communication system within 3GPP. In this operationexample, the HeNB 3003 is included in the tracking area of the MTCD_1,and thus performs the process of Step ST3203.

As described above, the user equipment 3009 whose MTCD identity isMTCD_1 is located within the coverage 3008 of the HeNB 3007, and thusreceives paging from the HeNB 3007 in Step ST3105. Therefore, the pagingfrom the HeNB 3005 in Step ST3107 and the paging from the HeNB 3003 inStep ST3203 become unnecessary.

The solution in the seventh embodiment is described below. The executionof the concentration process by the HeNB is registered with the MME,HSS, or the like being a core network, together with the MTCD identity.The information regarding whether or not to perform a concentrationprocess is also referred to as “concentration process situation” below.In a case where paging directed to an MTCD has occurred, theconcentration process situation is contained in the paging message. In acase of having received the paging message containing the informationindicating to perform the concentration process, the HeNB transmits thepaging message in a case where the own HeNB has the capability ofperforming a concentration process.

The following four (1) to (4) are disclosed as specific examples of thetiming of registering with a core network that a HeNB performs aconcentration process. (1) Every time a HeNB concentrates data from anMTCD being served thereby to a core network. (2) In a case of performinga concentration process on an attach message from an MTCD or in a caseof selecting “Attach procedure” in the concentration process. In thisspecific example (2), the number of times of registering with a corenetwork that a HeNB performs a concentration process is fewer than thatof the specific example (1). Accordingly, communication resources can beused effectively, leading to a reduction of the processing load of theHeNB. (3) In a case of performing a concentration process on a TAUmessage from an MTCD or in a case of selecting “Tracking Area Updateprocedure” in the concentration process. In this specific example (3),the number of times of registering with a core network that a HeNBperforms a concentration process is fewer than that of the specificexample (1). Accordingly, communication resources can be usedeffectively, leading to a reduction of the processing load of the HeNB.(4) Combination of (2) and (3) above.

One specific example of the timing of deleting the registration that acore network performs a concentration process is a time when the corenetwork receives “Detach procedure” from an MTCD. A specific example ofthe registration method is disclosed below. The core network stores aconcentration process situation in association with the MTCD identity.

The following two (1) and (2) are disclosed as specific examples of theentity for registration. (1) MME. In a case of processing an incomingcall, it is not required to inquire of another entity. This prevents acontrol delay and is effective in a reduction of the processing load ofa communication system. (2) HSS. This enables to store a concentrationprocess situation together with the other registration information andis effective in that data can be integrally managed. The specificexample (2) is more advantageous than the specific example (1) in thateven in a case where an MME changes upon moving of a user equipment, theregistration information can be used effectively. That is, the number oftimes of registering a concentration process with an HSS from a HeNB canbe reduced. This enables to effectively use communication resources,leading to a reduction of the processing load of a HeNB.

The following two (1) and (2) are disclosed as specific examples of themethod of causing, when paging occurs, a paging message to contain theinformation indicating that a concentration process has been performed.(1) In a case where a registration location is an HSS, a caller or anMME being a receiver inquires a concentration process situation of theHSS. The MME maps the inquiry results to a paging message. (2) In a casewhere a registration location is an MME, an MME being a receiversearches a concentration process situation of an MTCD to which anincoming call is made. The MME maps the search results to a pagingmessage.

A specific operation example using the seventh embodiment is describedwith reference to FIG. 35 and FIG. 36. FIG. 35 and FIG. 36 are diagramsshowing a sequence of a mobile communication system in the seventhembodiment. FIG. 35 and FIG. 36 are continuous from each other at aposition of a boundary A3. The steps of FIG. 35 and FIG. 36corresponding to the steps shown in FIG. 17, FIG. 26, FIG. 31, and FIG.32 are denoted by the same reference symbols, and the common descriptionis not given here.

In this operation example, description is given with reference to thelocation diagram shown in FIG. 30. The HeNB 3003 and HeNB 3007 are HeNBswith the capability of performing a concentration process, and the HeNB3005 is a HeNB without the capability of performing a concentrationprocess. The user equipment 3009 is an MTCD, and the MTCD identity isMTCD_1. As a specific example of the timing of registering with a corenetwork that a HeNB performs a concentration process, a case ofconcentrating attach messages of MTCDs is disclosed. In addition, a casein which a specific example of the entity for registration is an HSS isdisclosed. Further, a case in which the third embodiment is executed isdisclosed.

First, the MTCD_1 performs the process of Step ST1703, and the MTCD_nperforms the process of Step ST1704. Then, the HeNB 3007 that hasreceived “RRC Connection Requests” transmitted from the MTCD_1 andMTCD_n performs the processes of Step ST1705 and Step ST1707. Then, theMTCD_1 performs the process of Step ST2601, and the MTCD_n performs theprocess of Step ST2602. Then, in Step ST2603, the HeNB 3007 that hasreceived the attach messages transmitted from the MTCD_1 and MTCD_nperforms the concentration process on the attach message from theMTCD_1, which has been received in Step ST2601, and the attach messagefrom the MTCD_n, which has been received in Step ST2602. That is, theHeNB performs the concentration process on the attach messages.Accordingly, in this operation example, the HeNB 3007 registers with acore network that a concentration process is performed.

Then, in Step ST3301, the HeNB 3007 notifies the MME of the attachmessage concentrated through the concentration process in Step ST2603and of that a concentration process is performed. The attach messagecontains the identity of the MTCD_1 and the identity of the MTCD_n beingidentities of MTCDs that are targets of the concentration process, theidentity of the HeNB, and the TAI. The attach message may contain that aconcentration process is performed. The second embodiment, the firstmodification of the second embodiment, the second modification of thesecond embodiment, and the third modification of the second embodimentcan be used in this notification.

In Step ST3302, the MME notifies a home subscriber server (HSS) of theidentity of the MTCD_1 and the identity of the MTCD_n, which areidentities of MTCDs that have been received as attach messages, and ofthat a concentration process is performed.

In Step ST3303, the HSS registers and manages the identity of the MTCD_1and the identity of the MTCD_n that have been attached, and that theconcentration process is performed. In registration and management, theconcentration process situation is associated with the MTCD identity.The MME receives an incoming call directed to the MTCD_1 in Step ST2607,and then, the MME performs the process of Step ST2608.

Then, in Step ST3304, the MME inquires the concentration situation ofthe MTCD_1 of the HSS. In Step ST3305, the HSS reports the concentrationsituation of the MTCD_1 to the MME. The concentration process has beenperformed on the MTCD_1 in this operation example, and thus, the HSSreports that the concentration process is performed.

In Step ST3306, the MME judges whether or not the concentration processhas been performed on the MTCD_1 based on the concentration situationreport received in Step ST3305. In a case of judging that theconcentration process has been performed on the MTCD_1, the MME moves toStep ST3307. In a case of judging that the concentration process has notbeen performed on the MTCD_1, the MME moves to Step ST3101. In thisoperation example, the concentration process has been performed on theMTCD_1, and the HSS reports that the concentration process is performedin Step ST3305. Therefore, the MME judges that the concentration processhas been performed on the MTCD_1 and moves to Step ST3307.

In Step ST3307, the MME adds, to the paging message directed to theMTCD_1, that the concentration process has been performed. Therefore, inthis operation example in which the process of Step ST3307 is performed,the paging message directed to the MTCD_1, which is notified the HeNB3007 by the MME in Step ST3101, contains that the concentration processhas been performed in addition to the tracking area list of the MTCD_1and the identity of the MTCD_1. Similarly, the paging message directedto the MTCD_1, which is notified the HeNB 3005 by the MME in StepST3102, contains that the concentration process has been performed inaddition to the tracking area list of the MTCD_1 and the identity of theMTCD_1. Similarly, the paging message directed to the MTCD_1, which isnotified the HeNB 3003 by the MME in Step ST3103, contains that theconcentration process has been performed in addition to the trackingarea list of the MTCD_1 and the identity of the MTCD_1.

In Step ST3308, the HeNB 3007 judges whether or not the paging receivedin Step ST3101 includes that the concentration process has beenperformed. In a case of judging that the concentration process has beenperformed is included, the HeNB 3007 moves to Step ST3309. In a case ofjudging that the paging does not include the concentration process hasbeen performed, the HeNB 3007 moves to Step ST3104. In this operationexample, the paging received in Step ST3101 includes that theconcentration process has been performed. Therefore, the HeNB 3007 movesto Step ST3309 after the process of Step ST3308.

In Step ST3309, the HeNB 3007 judges whether or not the own HeNB has theconcentration processing capability. In a case of judging that the ownHeNB has the concentration processing capability, the HeNB 3007 moves toStep ST3104. In a case of judging that the own HeNB does not have theconcentration processing capability, the HeNB 3007 does not perform theprocesses of Step ST3104 and Step ST3105. In this operation example, theHeNB 3007 has the concentration processing capability, and thus moves toStep ST3104. Then, the HeNB 3007 performs the processes of Step ST3104and Step ST3105.

In Step ST3310, the HeNB 3005 judges whether or not the paging receivedin Step ST3102 includes that the concentration process has beenperformed. In a case of judging that the paging includes that theconcentration process has been performed, the HeNB 3005 moves to StepST3311. In a case of judging that the paging does not include theconcentration process has been performed, the HeNB 3005 moves to StepST3106. In this operation example, the paging received in Step ST3102includes that the concentration process has been performed. Accordingly,the HeNB 3005 moves to Step ST3311 after the process of Step ST3310.

In Step ST3311, the HeNB 3005 judges whether or not the own HeNB has theconcentration processing capability. In a case of judging that the ownHeNB has the concentration processing capability, the HeNB 3005 moves toStep ST3106. In a case of judging that the own HeNB does not have theconcentration processing capability, the HeNB 3005 does not perform theprocesses of Step ST3106 and Step ST3107. In this operation example, theHeNB 3005 does not have the concentration processing capability, andthus does not perform the processes of Step ST3106 and Step ST3107. InFIG. 31 and FIG. 32 for describing unused radio resources in a casewhere the third embodiment is executed, as shown in Step ST3107 of FIG.32, the HeNB 3005 notifies the unnecessary paging directed to theMTCD_1, which is not received by the MTCD_1. In the present embodiment,unnecessary paging as shown in Step ST3107 of FIG. 32 can be reduced.

In Step ST3312, the HeNB 3003 judges whether or not the paging receivedin Step ST3103 includes that the concentration process has beenperformed. In a case of judging that the concentration process has beenperformed is included, the HeNB 3003 moves to Step ST3313. In a case ofjudging that the paging does not include the concentration process hasbeen performed, the HeNB 3003 moves to Step ST3108. In this operationexample, the paging received in Step ST3103 includes that theconcentration process has been performed. Accordingly, the HeNB 3003moves to Step ST3313 after the process of Step ST3312.

In Step ST3313, the HeNB 3003 judges whether or not the own HeNB has theconcentration processing capability. In a case of judging that the ownHeNB has the concentration processing capability, the HeNB 3003 moves toStep ST3108. In a case of judging that the own HeNB does not have theconcentration processing capability, the HeNB 3003 does not perform theprocesses of Step ST3108 and Step ST3109. In this operation example, theHeNB 3003 has the concentration processing capability, and thus moves toStep ST3108. Then, the HeNB 3003 performs the processes of Step ST3108and Step ST3109.

A specific operation example using the seventh embodiment is describedwith reference to FIG. 37 and FIG. 38. FIG. 37 and FIG. 38 are diagramsshowing another sequence of the mobile communication system in theseventh embodiment. FIG. 37 and FIG. 38 are continuous from each otherat a position of a boundary A4. The steps of FIG. 37 and FIG. 38corresponding to the steps shown in FIG. 17, FIG. 26, and FIG. 31 toFIG. 36 are denoted by the same reference symbols, and the commondescription is not given here.

In this operation example, description is given with reference to thelocation diagram shown in FIG. 30. The HeNB 3003 and the HeNB 3007 areHeNBs with the capability of performing a concentration process, and theHeNB 3005 is a HeNB without the capability of performing a concentrationprocess. The user equipment 3009 is an MTCD and the MTCD identity isMTCD_1. As a specific example of the timing of registering with a corenetwork that a HeNB performs a concentration process, a case ofconcentrating attach messages of MTCDs is disclosed. In addition, a casein which a specific example of the entity for registration is an MME isdisclosed. Further, a case in which the third embodiment is executed isdisclosed.

First, the MTCD_1 performs the process of Step ST1703, and the MTCD_nperforms the process of Step ST1704. Then, the HeNB 3007 that hasreceived “RRC Connection Requests” transmitted from the MTCD_1 andMTCD_n performs the processes of Step ST1705 and Step ST1707. Then, theMTCD_1 performs the process of Step ST2601, and the MTCD_n performs theprocess of Step ST2602. Then, the HeNB 3007 that has received the attachmessages transmitted from the MTCD_1 and MTCD_n performs the processesof Step ST2603 and Step ST3301.

Then, in Step ST3401, the MME registers and manages the identity of theMTCD_1 and the identity of the MTCD_n, which are identities of MTCDsreceived through the attach message in Step ST3301. In registration andmanagement, the concentration process situation is associated with theMTCD identity. Then, the MME performs the process of Step ST2605, andthe HSS performs the process of Step ST2606. The MME receives anincoming call directed to the MTCD_1 in Step ST2607, and then, the MMEperforms the process of Step ST2608.

Then, in Step ST3402, the MME searches a concentration situation of theMTCD_1. After the process of Step ST3402, the MME performs the processesof Step ST3306, Step ST3307, and Step ST3101 to Step ST3103, as in FIG.36. The HeNB 3007 performs the processes of Step ST3308, Step ST3309,Step ST3104, and Step ST3105. The HeNB 3005 performs the processes ofStep ST3310, Step ST3311, Step ST3106, and Step ST3107. The HeNB 3003performs the processes of Step ST3312, Step ST3313, Step ST3108, andStep ST3109.

In this operation example, in Step ST3311, the HeNB 3005 judges whetheror not the own HeNB has the concentration processing capability, as inthe sequence shown in FIG. 36. In a case of judging that the own HeNBhas the concentration processing capability, the HeNB 3005 moves to StepST3106. In a case of judging that the own HeNB does not have theconcentration processing capability, the HeNB 3005 does not perform theprocesses of Step ST3106 and Step ST3107. In this operation example, theHeNB 3005 does not have the concentration processing capability, andthus does not perform the processes of Step ST3106 and Step ST3107. InFIG. 31 and FIG. 32 for describing unused radio resources in a case ofexecuting the third embodiment, as shown in Step ST3107 of FIG. 32, theHeNB 3005 notifies the unnecessary paging directed to the MTCD_1, whichis not received by the MTCD_1. In the present embodiment, unnecessarypaging as shown in Step ST3107 of FIG. 32 can be reduced.

A specific operation example using the seventh embodiment is describedwith reference to FIG. 39 and FIG. 40. FIG. 39 and FIG. 40 are diagramsshowing another sequence of a mobile communication system in the seventhembodiment. FIG. 39 and FIG. 40 are continuous from each other at aposition of a boundary A5. The steps of FIG. 39 and FIG. 40corresponding to the steps shown in FIG. 26, FIG. 27, and FIG. 31 toFIG. 36 are denoted by the same reference symbols, and the commondescription is not given here.

In this operation example, description is given with reference to thelocation diagram shown in FIG. 30. The HeNB 3003 and the HeNB 3007 areHeNBs with the capability of performing a concentration process, and theHeNB 3005 is a HeNB without the capability of performing a concentrationprocess. The user equipment 3009 is an MTCD and the MTCD identity isMTCD_1. As a specific example of the timing of registering with a corenetwork that a HeNB performs a concentration process, a case ofselecting “Attach procedure” in the concentration process is disclosed.In addition, a case in which a specific example of the entity forregistration is an HSS is disclosed. Further, a case in which the fourthembodiment is executed is disclosed.

First, the MTCD_1 performs the process of Step ST2701, and the MTCD_nperforms the process of Step ST2702. Then, the HeNB 3007 performs theprocesses of Step ST2703 and Step ST2704.

Then, in Step ST2705, the HeNB 3007 performs a concentration process. Inthis operation example, the HeNB 3007 collectively notifies the MME ofpieces of data from the MTCD_1 and the MTCD_n to the core network. TheHeNB 3007 interprets the contents of Step ST2701 and Step ST2702accessed outside 3GPP, and grasps the contents as the access related to“installation”. Then, the HeNB 3007 selects “Attach procedure” as theprotocol within 3GPP, which is in accordance with the access related to“installation”. The HeNB 3007 selects “Attach procedure” in theconcentration process. Accordingly, in this operation example, the HeNB3007 registers with the core network that the concentration process isperformed.

In Step ST3501, the HeNB 3007 notifies the MME of the attach messageconcentrated through the concentration process in Step ST2705, and ofthat the concentration process is performed. The attach message maycontain the identity of the MTCD_1 and the identity of the MTCD_n, whichare identities of MTCDs being targets of the concentration process, theidentity of the HeNB, and the TAI. The attach message may contain thatthe concentration process is performed. The second embodiment, the firstmodification of the second embodiment, the second modification of thesecond embodiment, and the third modification of the second embodimentcan be used in this notification.

After the process of Step ST3501, the MME performs the processes of StepST3302, Step ST2608, Step ST3304, Step ST3306, Step ST3307, and StepST3101 to Step ST3103. The HSS performs the processes of Step ST3303,Step ST2607, and Step ST3305. The HeNB 3007 performs the processes ofStep ST3308, Step ST3309, Step ST2707, Step ST2708, Step ST2709, andStep ST2710. The HeNB 3005 performs the processes of Step ST3310, StepST3311, Step ST3106, and Step ST3107. The HeNB 3003 performs theprocesses of Step ST3312, Step ST3313, Step ST3201, Step ST3109, StepST3202, and Step ST3203.

In Step ST3310, the HeNB 3005 judges whether or not the paging receivedin Step ST3102 includes that the concentration process has beenperformed. In a case of judging that the paging includes that theconcentration process has been performed, the HeNB 3005 moves to StepST3311. In a case of judging that the paging does not include theconcentration process has been performed, the HeNB 3005 moves to StepST3106. In this operation example, the paging received in Step ST3102includes that the concentration process has been performed. Accordingly,the HeNB 3005 moves to Step ST3311 after the process of Step ST3310.

In Step ST3311, the HeNB 3005 judges whether or not the own HeNB has theconcentration processing capability. In a case of judging that the ownHeNB has the concentration processing capability, the HeNB 3005 moves toStep ST3106. In a case of judging that the own HeNB does not have theconcentration processing capability, the HeNB 3005 does not perform theprocesses of Step ST3106 and Step ST3107. In this operation example, theHeNB 3005 does not have the concentration processing capability, andthus does not perform the processes of Step ST3106 and Step ST3107. InFIG. 33 and FIG. 34 for describing unused radio resources in a casewhere the fourth embodiment is executed, as shown in Step ST3107 of FIG.34, the HeNB 3005 notifies the unnecessary paging directed to theMTCD_1, which is not received by the MTCD_1. In the present embodiment,unnecessary paging as shown in Step ST3107 of FIG. 34 can be reduced.

A specific operation example using the seventh embodiment is describedwith reference to FIG. 41 and FIG. 42. FIG. 41 and FIG. 42 are diagramsshowing another sequence of the mobile communication system in theseventh embodiment. FIG. 41 and FIG. 42 are continuous from each otherat a position of a boundary A6. The steps of FIG. 41 and FIG. 42corresponding to the steps shown in FIG. 26, FIG. 27, FIG. 31 to FIG.36, FIG. 39, and FIG. 40 are denoted by the same reference symbols, andthe common description is not given here.

In this operation example, description is given with reference to thelocation diagram shown in FIG. 30 above. The HeNB 3003 and the HeNB 3007are HeNBs with the capability of performing a concentration process, andthe HeNB 3005 is a HeNB without the capability of performing aconcentration process. The user equipment 3009 is an MTCD and the MTCDidentity is MTCD_1. As a specific example of the timing of registeringwith a core network that a HeNB performs a concentration process, a caseof concentrating attach messages of MTCDs is disclosed. In addition, acase in which a specific example of the entity for registration is anMME is disclosed. Further, a case in which the fourth embodiment isexecuted is disclosed.

In this operation example, in Step ST3311, the HeNB 3005 judges whetheror not the own HeNB has the concentration processing capability, as inthe sequence shown in FIG. 39 and FIG. 40. In a case of judging that theown HeNB has the concentration processing capability, the HeNB 3005moves to Step ST3106. In a case of judging that the own HeNB does nothave the concentration processing capability, the HeNB 3005 does notperform the processes of Step ST3106 and Step ST3107. In this operationexample, the HeNB 3005 does not have the concentration processingcapability, and thus does not perform the processes of Step ST3106 andStep ST3107. In FIG. 33 and FIG. 34 for describing unused radioresources in a case where the fourth embodiment is executed, as shown inStep ST3107 of FIG. 34, the HeNB 3005 notifies the unnecessary pagingdirected to the MTCD_1, which is not received by the MTCD_1. In thepresent embodiment, unnecessary paging as shown in Step ST3107 of FIG.34 can be reduced.

The seventh embodiment can achieve the following effects in addition tothe effects of the third embodiment and the fourth embodiment. In a caseof receiving a paging message containing the information indicating thata concentration process is performed, the HeNB transmits the pagingmessage if the own HeNB has the capability of performing a concentrationprocess. This enables to reduce the notification of the paging directedto the MTCD, on which a concentration process is performed, by a HeNBwithout the capability of performing a concentration process. An MTCD,to be served by a HeNB without concentration processing capability, onwhich the concentration process is performed will not be located. Thisenables to reduce only the transmission of unnecessary paging from aHeNB and effectively use radio resources while preventing an oversightof incoming calls. Accordingly, interference can be reduced.

First Modification of Seventh Embodiment

A solution to be solved in a first modification of the seventhembodiment is described below. In a case where the seventh embodiment isused, the following problem occurs. The problem is described withreference to FIG. 36. The use of the seventh embodiment enables toreduce the notification of the paging directed to the MTCD, on which aconcentration process is performed, by a HeNB without the capability ofperforming a concentration process. Meanwhile, for example in StepST3102 of FIG. 36, a paging message, which is not notified a HeNBwithout the capability of performing a concentration process, isnotified. This causes a problem that unused communication resources aregenerated, and in Step ST3310, Step ST3311, and the like of FIG. 36,unnecessary processing load occurs in an MME or a HeNB without thecapability of performing a concentration process.

A solution in the first modification of the seventh embodiment isdescribed below. A portion different from the solution of the seventhembodiment is mainly described. A portion that is not described here isas in the seventh embodiment.

That a HeNB performs a concentration process is registered with an MME,HSS, or the like being a core network, together with the MTCD identity.The information regarding whether or not to perform a concentrationprocess is also referred to as “concentration process situation”. In acase where paging directed to an MTCD, on which a concentration processis performed, occurs, the MME transmits a paging message to a HeNB withthe capability of performing a concentration process. In a case wherepaging directed to an MTCD, on which a concentration process isperformed, occurs, the MME does not transmit a paging message to a HeNBwithout the capability of performing a concentration process.

A specific example in which an MME grasps the capability of performing aconcentration process by a HeNB being served thereby is disclosed below.With the third modification of the first embodiment described above, aHeNB notifies an MME, SGSN, or the like being a core network of thecapability information regarding the concentration process for the datafrom an MTCD.

A specific operation example using the first modification of seventhembodiment is described with reference to FIG. 43 and FIG. 44. FIG. 43and FIG. 44 are diagrams showing a sequence of a mobile communicationsystem in the first modification of the seventh embodiment. FIG. 43 andFIG. 44 are continuous from each other at a position of a boundary A7.The steps of FIG. 43 and FIG. 44 corresponding to the steps shown inFIG. 17, FIG. 26, FIG. 31, FIG. 32, FIG. 35, and FIG. 36 are denoted bythe same reference symbols, and the common description is not givenhere.

In this operation example, description is given with reference to thelocation diagram shown in FIG. 30 above. The HeNB 3003 and the HeNB 3007are HeNBs with the capability of performing a concentration process, andthe HeNB 3005 is a HeNB without the capability of performing aconcentration process. The user equipment 3009 is an MTCD and the MTCDidentity is MTCD_1. As a specific example of the timing at which a HeNBnotifies a core network of the capability information regarding theconcentration process, a time when a HeNB is installed is disclosed. Asa specific example of the timing of registering with a core network thata HeNB performs a concentration process, a case of concentrating attachmessages of MTCDs is disclosed. In addition, a case in which a specificexample of the entity for registration is an HSS is disclosed. Further,a case in which the third embodiment is executed is disclosed.

In Step ST3701, the HeNB 3007 is installed. In Step ST3702, the HeNB3007 notifies the MME of the capability information regarding theconcentration process by the HeNB 3007.

In Step ST3703, the HeNB 3005 is installed. In Step ST3704, the HeNB3005 notifies the MME of the capability information regarding theconcentration process by the HeNB 3005.

In Step ST3705, the HeNB 3003 is installed. In Step ST3706, the HeNB3003 notifies the MME of the capability information regarding theconcentration process of the HeNB 3003.

In Step ST3707, the MME registers and manages pieces of capabilityinformation of the HeNBs being served thereby. In registration andmanagement, the capability information is associated with the HeNBidentity.

In Step ST3306, the MME judges whether or not that the concentrationprocess has been performed on the MTCD_1 based on the concentrationsituation report received in Step ST3305. In a case of judging that theconcentration process has been performed on the MTCD_1, the MME moves toStep ST3708. In a case of judging that the concentration process has notbeen performed on the MTCD_1, the MME moves to Step ST3101. In thisoperation example, the concentration process has been performed on theMTCD_1, and it is reported that the concentration process is performedin Step ST3305. Therefore, the MME judges that the concentration processhas been performed on the MTCD_1 and moves to Step ST3708.

In Step ST3708, the MME selects a HeNB with the capability of performinga concentration process from HeNBs being served thereby. The informationregistered in Step ST3707 may be used in the selection. In thisoperation example, the HeNB 3003 and the HeNB 3007 are selected as HeNBswith the capability of performing a concentration process. Meanwhile,the HeNB 3005 is not selected as a HeNB with the capability ofperforming a concentration process. The MME transmits a paging messageto the HeNBs with the capability of performing a concentration processand does not transmit a paging message to the HeNB without thecapability of performing a concentration process.

Accordingly, in Step ST3101, the MME notifies the HeNB 3007 of pagingdirected to the MTCD_1. This paging includes the tracking area list ofthe MTCD_1 and the identity of the MTCD_1. In Step ST3103, the MMEnotifies the HeNB 3003 of the paging directed to the MTCD_1. This pagingincludes the tracking area list of the MTCD_1 and the identity of theMTCD_1. The MME does not notify the HeNB 3005 of the paging directed tothe MTCD_1. In FIG. 36, the MME notifies the HeNB 3005 of the pagingmessage that is not notified, as shown in Step ST3102. The presentembodiment can reduce unnecessary communication as shown in Step ST3102of FIG. 36.

Meanwhile, in a case where the MME judges that the concentration processhas not been performed on a user equipment to which an incoming call hadbeen made in Step ST3306, in Step ST3101, the MME notifies the HeNB 3007of the paging directed to the MTCD_1. This paging includes the trackingarea list of the MTCD_1 and the identity of the MTCD_1. In Step ST3102,the MME notifies the HeNB 3005 of the paging directed to the MTCD_1.This paging includes the tracking area list of the MTCD_1 and theidentity of the MTCD_1. In Step ST3103, the MME notifies the HeNB 3003of the paging directed to the MTCD_1. This paging includes the trackingarea list of the MTCD_1 and the identity of the MTCD_1.

While the present modification has mainly described an example incombination with the third embodiment, the present modification can beused also in combination with the fourth embodiment.

The first modification of the seventh embodiment can achieve thefollowing effects in addition to the effects of the seventh embodiment.In a case of receiving a paging message directed to an MTCD on which aconcentration process is performed, the MME transmits a paging messageto a HeNB with the capability of performing a concentration process.This enables to reduce the notification of the paging directed to theMTCD, on which a concentration process is performed, for a HeNB withoutthe capability of performing a concentration process. An MTCD, to beserved by a HeNB without the concentration processing capability, onwhich a concentration process is performed will not be located. Thisenables to reduce only the notification of unnecessary paging for a HeNBand effectively use radio resources while preventing an oversight ofincoming calls. Accordingly, the processing load of an MME or a HeNBwithout the capability of performing a concentration process can bereduced.

Second Modification of Seventh Embodiment

A problem to be solved by a second modification of the seventhembodiment is described below. In the case where the seventh embodiment,the following problem occurs. The problem is described with reference toFIG. 35 and FIG. 36. The use of the seventh embodiment enables to reducethe notification of paging directed to an MTCD, on which a concentrationprocess is performed, by a HeNB without the capability of performing aconcentration process. Meanwhile, paging directed to a HeNB to an MTCD,on which a concentration process is not performed, is still notified asshown in Step ST3103 and Step ST3109 in FIG. 36. The meaningless pagingtransmission has a problem that radio resources cannot be usedeffectively and interference occurs.

A solution in the second modification of the seventh embodiment isdescribed below. A HeNB registers the identity of a HeNB that hasperformed a concentration process with an MME, HSS, or the like being acore network, together with an MTCD identity.

In a case where paging directed to an MTCD occurs as in the seventhembodiment, a paging message contains the identity of the HeNB that hasperformed a concentration process. In a case where a HeNB receives thepaging message containing the identity of the HeNB that has performed aconcentration process, the HeNB transmits the paging message if theidentity of the HeNB is that of the own HeNB.

A specific example of the timing at which a HeNB registers the identityof the HeNB that has performed a concentration process with the corenetwork is similar to a specific example of the “timing of registeringwith a core network that a HeNB performs a concentration process” in theseventh embodiment, which is not described here.

Specific examples of the timing at which a core network deletes theregistration of the identity of the HeNB that has performed aconcentration process include a time of receiving “Detach procedure”from an MTCD.

A specific example of the registration method is described below. Theidentity of the HeNB that has performed a concentration process isstored in association with the MTCD identity.

A specific example of an entity for registration is similar to that ofthe seventh embodiment, which is not described here. A specific exampleof the method of causing a paging message to contain the identity of theHeNB that has performed a concentration process when paging has occurredis similar to a specific example of the method of causing a pagingmessage to contain the information indicating that a concentrationprocess has been performed when paging has occurred in the seventhembodiment, which is not descried here.

Alternatively, as in the first modification of the seventh embodiment,when paging directed to an MTCD on which a concentration process isperformed occurs, an MME transmits a paging message to a HeNB that hasperformed a concentration process. In a case where paging directed to anMTCD on which a concentration process is performed occurs, an MME doesnot transmit a paging message to HeNBs other than the HeNB that hasperformed the concentration process.

The second modification of the seventh embodiment can achieve thefollowing effects in addition to the effects of the seventh embodimentand the first modification of the seventh embodiment.

It is possible to reduce paging directed to an MTCD from a HeNB otherthan a HeNB that has performed a concentration process. Alternatively,it is possible to reduce paging notification to a HeNB other than theHeNB that has performed a concentration process. An MTCD, to be servedby a HeNB other than the HeNB that has performed the concentrationprocess, on which a concentration process is performed will not belocated. This enables to reduce only unnecessary paging from a HeNB orthe notification of unnecessary paging for a HeNB and effectively useradio resources while preventing an oversight of incoming calls.Accordingly, communication resources can be used effectively. Further,the processing load of an MME or a HeNB without the capability ofperforming a concentration process can be reduced.

The methods disclosed in the present invention are applicable not onlyto eNBs/NBs, but also to so-called local nodes such as HeNB, HNB, picoeNB (LTE pico cell (EUTRAN pico cell)), pico NB (WCDMA pico cell (UTRANpico cell)), and node for hotzone cells. The methods disclosed in thepresent invention are performed on a local node that supports MTCservice, which enables to avoid congestion in a core network.

While the LTE system (E-UTRAN) has been mainly described in therespective embodiments, the communication system of the presentinvention is also applicable to the W-CDMA system (UTRAN, UMTS) andLTE-Advanced.

While the invention has been shown and described in detail, theforegoing description is in all aspects illustrative and notrestrictive. It is therefore understood that numerous modifications andvariations can be devised without departing from the scope of theinvention.

DESCRIPTION OF REFERENCE SYMBOLS

1301 to 1304 MTCD, 1305 NB/eNB, 1306 SGSN/MME, 1307 HLR/HSS, 1308 MTCserver, 1309 MTC user, 1310 API, 1311 to 1314 Uu interface, 1315 IuPS/S1interface, 1316 Gr/S6a interface, 1317 communication operator domain,3001, 3010 eNB, 3003, 3005, 3007, 3012, 3014 HeNB, 3002, 3004, 3006,3008, 3011, 3013, 3015 coverage, 3009 user equipment, 3016 tracking area#1 (TA #1), 3017 tracking area #2 (TA #2).

1. A mobile communication system in which a communication terminaldevice and a base station device mutually perform radio communication,wherein when communication cannot be performed between the communicationterminal device and the base station device, an upper device is notifiedby the base station device that the communication cannot be performed.2. The mobile communication system according to claim 1, wherein thecommunication terminal device is a communication terminal device formachine-to-machine (M2M) communication.
 3. The mobile communicationsystem according to claim 1, wherein when the base station device ischanged, the base station device is notified by the upper device thatthe base station device is changed.
 4. The mobile communication systemaccording to claim 3, wherein the base station device is notified of anidentification code for identifying the communication terminal device bythe upper device while being notified that the base station device ischanged.
 5. The mobile communication system according to claim 3,wherein when the base station device is notified that the base stationdevice is changed, the base station device finishes communication withthe communication terminal device.
 6. A base station device thatmutually performs radio communication with a communication terminaldevice, wherein when communication with the communication terminaldevice cannot be performed, an upper device is notified by the basestation device that the communication cannot be performed.
 7. An upperdevice controlling a base station device mutual performing radiocommunication with a communication terminal device, wherein whencommunication cannot be performed between the communication terminaldevice and the base station device, the upper device receives a signalfor notifying by the base station that the communication cannot beperformed.